Catechol protected levodopa diester prodrugs, compositions, and methods of use

ABSTRACT

Catechol protected levodopa diester prodrugs pharmaceutical, compositions comprising catechol protected levodopa diester prodrugs, and methods of using such prodrugs and pharmaceutical compositions for treating diseases such as Parkinson&#39;s disease are provided.

This application claims the benefit under 35 U.S.C. § 119(e) of U.S.Provisional Application Ser. No. 60/876,148 filed Dec. 21, 2006, andU.S. Provisional Application Ser. No. 60/993,085 filed Sep. 7, 2007,each of which is incorporated by reference herein in its entirety.

FIELD

Disclosed herein are catechol protected levodopa diester prodrugs, andpharmaceutical compositions comprising catechol protected levodopadiester prodrugs, useful for treating diseases such as Parkinson'sdisease.

BACKGROUND

Parkinson's disease is a disabling, progressive illness that affects onein 1,000 people and generally occurs in people over the age of 50 years.Patients with Parkinson's disease have a deficiency of theneurotransmitter dopamine in the brain as a result of nigrostriatalpathway disruption caused by degeneration of the substantia nigra.Levodopa (L-dopa or L-3,4-dihydroxyphenylalanine), an immediateprecursor of dopamine, is the most commonly prescribed drug fortreatment of this disease.

Following oral administration, levodopa is rapidly absorbed via an aminoacid transporter present in the upper small intestine. Due to the narrowdistribution of this transporter system, the window available forlevodopa absorption is limited and the extent of absorption can dependon the rate at which the drug passes through the upper gastrointestinaltract.

Intestinal metabolism of levodopa is the major source of first pass lossof the drug. Approximately 35% of an administered dose of levodopareaches the systemic circulation as intact levodopa after oraladministration in patients (Sasahara, J. Pharm. Sci 1990, 69, 261). Onceabsorbed, levodopa is rapidly metabolized to dopamine by L-aromaticamino acid decarboxylase (AADC) enzymes in the peripheral tissues (e.g.,intestines and liver). For this reason, levodopa is normallyco-administered with a decarboxylase enzyme inhibitor such as carbidopaor benserazide. When administered with carbidopa, the plasmaconcentration of intact levodopa increases and thus more levodopabecomes available to be transported into the central nervous systemwhere it is converted to dopamine. Carbidopa and benserazide do notcross the blood-brain barrier to a significant extent and therefore donot inhibit the required conversion of levodopa to dopamine in thebrain.

The use of prodrugs of levodopa to improve the pharmacokinetics oflevodopa has been proposed. Many of these prodrugs are simple esters oflevodopa (see e.g., Chiesi, U.S. Pat. Nos. 5,017,607 and 4,826,875;Repta, U.S. Pat. Nos. 4,873,263, 4,771,073, and 4,663,349; Bodor et al.,U.S. Pat. No. 4,311,706; Konishi and lenaga, Japanese Patent No.JP58024547; Juncos et al., Neurology 1987, 37, 1242; and Cooper et al.,J. Pharm. Pharmacol. 1987, 39, 627-635). An oral formulation of levodopamethyl ester (Levomet®, CHF 1301) has been described (ChiesiPharmaceuticals). The ethyl ester of levodopa (TV-1203) is underclinical investigation as a potential therapy for Parkinson's diseasewhen co-administered with carbidopa (Milman et al., U.S. Pat. No.5,607,969). A sustained release cellulose formulation of levodopa ethylester in a mixture of hydroxypropylmethyl cellulose, hydroxypropylcellulose, and a carboxyvinyl polymer has also been described (Cohen etal., U.S. Pat. No. 5,840,756). However, oral administration of thisformulation to healthy adults pretreated with carbidopa produced aplasma levodopa terminal half-life of only 2 hours, comparable to thatof Sinemet® CR.

A pivaloyl ester of levodopa (NB-355) has been described (Tsuchiya andHayashi, European Patent No. 0 309 827). Following oral administrationof NB-355, a rapid increase in the plasma concentration or in theelimination of levodopa was not observed and the duration of circulatinglevodopa was prolonged, although plasma concentrations of levodopa werelow. The potential for using ester prodrugs of levodopa to enhancerectal absorption of the drug has also been described (Repta, U.S. Pat.Nos. 4,663,349, 4,771,073, and 4,873,263). Notably, the absorption ofsimple alkyl esters of levodopa has been shown to be greater followingrectal absorption than following oral dosing (Fix, et al., Pharm. Res.1989, 6, 501-5; and Fix, et al., Pharm. Res. 1990, 4, 384-7). Thiseffect is attributed to the decreased abundance of esterases in thelarge intestine relative to the small intestine. Therefore, selectivedelivery of a prodrug of levodopa to the large intestine in a sustainedrelease formulation might be expected to provide a greater oralbioavailability and a prolonged systemic exposure to the drug. A seriesof glycolic acid ester containing prodrugs of levodopa has beendescribed (Wermuth, U.S. Pat. No. 4,134,991). Lipid conjugates oflevodopa to facilitate the entry of levodopa into cells and tissues havealso been described (Yatvin, U.S. Pat. No. 5,827,819). Glyercolderivatives of levodopa are described by Dumont, InternationalApplication Publication No. WO 86/04579. Catechol protected levodopaderivatives intended to provide sustained clinically effective bloodconcentrations of levodopa are disclosed in Tsuchiya et al., U.S. Pat.No. 4,966,915.

Thus, the development of levodopa prodrugs that can be efficientlyabsorbed throughout the gastrointestinal tract, including the colon, andreduce first-pass metabolism of levodopa is highly desirable.

The human gastrointestinal tract includes the small intestine and thelarge intestine. The human small intestine is a convoluted tube abouttwenty feet in length between the stomach and large intestine. The smallintestine is subdivided into the duodenum, the jejunum, and the ileum.The large intestine is about 5 feet in length and runs from the ileum tothe anus. The large intestine is divided into the caecum, colon, and therectum. The colon is divided into four parts including the ascending,traverse, descending, and the sigmoid flexure. In general, an orallyingested compound resides about 1 to 6 hours in the stomach, about 2 to7 hours in the small intestine, and about 8 to 18 hours in the colon.Thus, the greatest period of time for sustained release of a compoundoccurs when the compound is passing through the colon.

Certain active transporter proteins are known to be expressed throughoutthe gastrointestinal tract. An active transporter refers to amembrane-bound protein that recognizes a substrate and affects the entryof the substrate into or exit from a cell by carrier-mediated transportor receptor-mediated transport. Active transport includes movement ofmolecules across cellular membranes that is directly or indirectlydependent on an energy mediated process, such as for example by aprocess driven by ATP hydrolysis, or by an ion gradient, which occurs byfacilitated diffusion mediated by interaction with specific transporterproteins through a modulated solute channel. Examples of solute mediatedtransporters include organic cation transporters such as OCTN1 andOCTN2, which are expressed in the epithelial cells lining a human colonas well as in the small intestine.

More recently, levodopa prodrugs designed to be absorbed in both thesmall and large intestines have been described in Xiang et al., U.S.Application Publication Nos. 2005/0282891 and 2006/0020028, each ofwhich is incorporated by reference herein in its entirety. Theselevodopa prodrugs can achieve a bioavailability of levodopa that is atleast two times greater than the bioavailability of levodopa whenintracolonically administered on an equivalent molar basis. The mesylatesalt of one of these prodrugs, (2R)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-(3,4-dihydroxyphenyl)propanoate mesylate, and crystallineforms thereof are described in Xiang et al., U.S. ApplicationPublication No. 2007/0225366. The prodrugs described by Xiang et al. canbe efficaciously incorporated into sustained release formulationsincluding osmotic delivery devices to provide sustained systemicexposure to levodopa upon oral administration to a patient.

SUMMARY

Accordingly, a need exists for levodopa prodrugs and crystalline formsthereof exhibiting physicochemical properties that may be usedadvantageously in pharmaceutical processing and pharmaceuticalcompositions, and that are also sufficiently labile under physiologicalconditions to provide therapeutically effective plasma concentrations oflevodopa, particularly when the levodopa prodrug is orally administered.

In a first aspect, compounds are provided having Formula (I):

stereoisomers thereof, pharmaceutically acceptable salts of any of theforegoing, or pharmaceutically acceptable solvates of any of theforegoing, wherein:

R¹ is chosen from C₁₋₈ alkyl, substituted C₁₋₈ alkyl, C₁₋₈ alkoxy,substituted C₁₋₈ alkoxy, C₃₋₇ cycloalkyl, substituted C₃₋₇ cycloalkyl,C₃₋₇ cycloalkoxy, substituted C₃₋₇ cycloalkoxy, phenyl, substitutedphenyl, phenyloxy, and substituted phenyloxy;

R² and R³ are independently chosen from C₁₋₈ alkyl, substituted C₁₋₈alkyl, C₁₋₈ alkoxy, substituted C₁₋₈ alkoxy, C₃₋₇ cycloalkyl, andsubstituted C₃₋₇ cycloalkyl; and R⁴ and R⁵ are independently chosen fromhydrogen, C₁₋₈ alkyl, and substituted C₁₋₈ alkyl;

wherein each substituent group is independently chosen from halogen,—OH, —COOH, —CN, —CF₃, ═O, —NO₂, C₁₋₃ alkoxy, C₁₋₃ alkyl, and —NR¹⁰ ₂wherein each R¹⁰ is independently chosen from hydrogen and C₁₋₃ alkyl.

In a second aspect, pharmaceutical compositions are provided comprisingat least one pharmaceutically acceptable vehicle and a therapeuticallyeffective amount of at least one compound of Formula (I) for treating adisease in a patient.

In a third aspect, methods of treating a disease in a patient areprovided comprising administering to a patient in need of such treatmenta pharmaceutical composition comprising at least one compound of Formula(I).

DETAILED DESCRIPTION Definitions

A dash (“-”) that is not between two letters or symbols is used toindicate a point of attachment for a substituent. For example, —CONH₂ isattached through the carbon atom.

“Alkyl” by itself or as part of another substituent refers to asaturated or unsaturated, branched or straight-chain, monovalenthydrocarbon radical derived by the removal of one hydrogen atom from asingle carbon atom of a parent alkane, alkene, or alkyne. Examples ofalkyl groups include, but are not limited to, methyl; ethyls such asethanyl, ethenyl, and ethynyl; propyls such as propan-1-yl, propan-2-yl,prop-1-en-1-yl, prop-1-en-2-yl, prop-2-en-1-yl (allyl), prop-1-yn-1-yl,prop-2-yn-1-yl, etc.; butyls such as butan-1-yl, butan-2-yl,2-methyl-propan-1-yl, 2-methyl-propan-2-yl, but-1-en-1-yl,but-1-en-2-yl, 2-methyl-prop-1-en-1-yl, but-2-en-1-yl, but-2-en-2-yl,buta-1,3-dien-1-yl, buta-1,3-dien-2-yl, but-1-yn-1-yl, but-1-yn-3-yl,but-3-yn-1-yl, etc.; and the like.

The term “alkyl” is specifically intended to include groups having anydegree or level of saturation, i.e., groups having exclusively singlecarbon-carbon bonds, groups having one or more double carbon-carbonbonds, groups having one or more triple carbon-carbon bonds, and groupshaving mixtures of single, double, and triple carbon-carbon bonds. Wherea specific level of saturation is intended, the terms “alkanyl,”“alkenyl,” and “alkynyl” are used. In certain embodiments, an alkylgroup can have from 1 to 20 carbon atoms, in certain embodiments, from 1to 10 carbon atoms, and in certain embodiments, from 1 to 8, from 1 to 5carbon atoms, or from 1 to 3 carbon atoms.

“Alkoxy” by itself or as part of another substituent refers to a radical—OR³¹ where R³¹ is chosen from alkyl, cycloalkyl, cycloalkylalkyl, aryl,and arylalkyl, which can be substituted, as defined herein. In someembodiments, alkoxy groups have from 1 to 8 carbons, from 1 to 5 carbonatoms, or from 1 to 3 carbon atoms. Examples of alkoxy groups include,but are not limited to, methoxy, ethoxy, propoxy, butoxy, cyclohexyloxy,and the like.

“Aryl” by itself or as part of another substituent refers to amonovalent aromatic hydrocarbon radical derived by the removal of onehydrogen atom from a single carbon atom of a parent aromatic ringsystem. Aryl encompasses 5- and 6-membered carbocyclic aromatic rings,for example, benzene; bicyclic ring systems wherein at least one ring iscarbocyclic and aromatic, for example, naphthalene, indane, andtetralin; and tricyclic ring systems wherein at least one ring iscarbocyclic and aromatic, for example, fluorene. Aryl encompassesmultiple ring systems having at least one carbocyclic aromatic ringfused to at least one carbocyclic aromatic ring, cycloalkyl ring, orheterocycloalkyl ring. For example, aryl includes 5- and 6-memberedcarbocyclic aromatic rings fused to a 5- to 7-membered heterocycloalkylring containing one or more heteroatoms chosen from N, O, and S. Forsuch fused, bicyclic ring systems wherein only one of the rings is acarbocyclic aromatic ring, the point of attachment may be at thecarbocyclic aromatic ring or the heterocycloalkyl ring. Examples of arylgroups include, but are not limited to, groups derived fromaceanthrylene, acenaphthylene, acephenanthrylene, anthracene, azulene,benzene, chrysene, coronene, fluoranthene, fluorene, hexacene,hexaphene, hexylene, as-indacene, s-indacene, indane, indene,naphthalene, octacene, octaphene, octalene, ovalene, penta-2,4-diene,pentacene, pentalene, pentaphene, perylene, phenalene, phenanthrene,picene, pleiadene, pyrene, pyranthrene, rubicene, triphenylene,trinaphthalene, and the like. In certain embodiments, an aryl group canhave from 5 to 20 carbon atoms, and in certain embodiments, from 5 to 12carbon atoms. Aryl, however, does not encompass or overlap in any waywith heteroaryl, separately defined herein. Hence, a multiple ringsystem in which one or more carbocyclic aromatic rings is fused to aheterocycloalkyl aromatic ring, is heteroaryl, not aryl, as definedherein. In certain embodiments, an aryl group is phenyl.

“AUC” is the area under a curve representing the concentration of acompound or metabolite thereof in a biological fluid in a patient as afunction of time following administration of the compound to thepatient. In certain embodiments, the compound can be a prodrug and themetabolite can be a drug. Examples of biological fluids include bloodand plasma. The AUC may be determined by measuring the concentration ofa compound or metabolite thereof in a biological fluid such as theplasma or blood using methods such as liquid chromatography-tandem massspectrometry (LC/MS/MS), at various time intervals, and calculating thearea under the plasma concentration-versus-time curve. Suitable methodsfor calculating the AUC from a drug concentration-versus-time curve arewell known in the art. As relevant to the disclosure herein, an AUC forlevodopa may be determined by measuring the concentration of levodopa inthe plasma or blood of a patient following oral administration of adosage form comprising a compound of Formula (I) or crystalline formthereof.

“Bioavailability” refers to the amount of a drug that reaches thesystemic circulation of a patient following administration of the drugor prodrug thereof to the patient and may be determined by evaluating,for example, the plasma or blood concentration-versus-time profile for adrug. Parameters useful in characterizing a plasma or bloodconcentration-versus-time curve include the area under the curve (AUC),the time to maximum concentration (T_(max)), and the maximum drugconcentration (C_(max)),

where C_(max) is the maximum concentration of a drug in the plasma orblood of a patient following administration of a dose of the drug orprodrug thereof to the patient, and T_(max) is the time to the maximumconcentration (C_(max)) of a drug in the plasma or blood of a patientfollowing administration of a dose of the drug or prodrug thereof to thepatient.

“Compounds” refers to compounds encompassed by structural Formula (I)disclosed herein and includes any specific compounds within theseformulae whose structure is disclosed herein. Compounds may beidentified either by their chemical structure and/or chemical name. Whenthe chemical structure and chemical name conflict, the chemicalstructure is determinative of the identity of the compound.

The compounds described herein may contain one or more chiral centersand/or double bonds and therefore may exist as stereoisomers such asdouble-bond isomers (i.e., geometric isomers), enantiomers, ordiastereomers. Accordingly, any chemical structures within the scope ofthe specification depicted, in whole or in part, with a relativeconfiguration encompass all possible enantiomers and stereoisomers ofthe illustrated compounds including the stereoisomerically pure form(e.g., geometrically pure, enantiomerically pure, or diastereomericallypure) and enantiomeric and stereoisomeric mixtures. Enantiomeric andstereoisomeric mixtures can be resolved into their component enantiomersor stereoisomers using separation techniques or chiral synthesistechniques well known to the skilled artisan.

Compounds of Formula (I) include, but are not limited to, opticalisomers of compounds of Formula (I), racemates thereof, and othercombinations thereof. In such embodiments, the single enantiomers ordiastereomers, i.e., optically active forms, can be obtained byasymmetric synthesis or by resolution of the racemates. Resolution ofthe racemates can be accomplished, for example, by conventional methodssuch as crystallization in the presence of a resolving agent, orchromatography, using, for example a chiral high-pressure liquidchromatography (HPLC) column. In addition, compounds of Formula (I)include Z- and E-forms (e.g., cis- and trans-forms) of compounds withdouble bonds. In embodiments in which compounds of Formula (I) exist invarious tautomeric forms, compounds of the present disclosure includeall tautomeric forms of the compound.

Compounds of Formula (I) may also exist in several tautomeric formsincluding the enol form, the keto form, and mixtures thereof.Accordingly, the chemical structures depicted herein encompass allpossible tautomeric forms of the illustrated compounds. The compounds ofFormula (I) also include isotopically labeled compounds where one ormore atoms have an atomic mass different from the atomic massconventionally found in nature. Examples of isotopes that may beincorporated into the compounds disclosed herein include, but are notlimited to, ²H, ³H, ¹¹C, ¹³C, ¹⁴C, ¹⁵N, ¹⁸O, ¹⁷O, etc. Compounds mayexist in unsolvated forms as well as solvated forms, including hydratedforms and as N-oxides. In general, compounds may be hydrated, solvated,or N-oxides. Certain compounds may exist in single or multiplecrystalline or amorphous forms. In general, all physical forms areequivalent for the uses contemplated herein and are intended to bewithin the scope of the present disclosure.

Further, when partial structures of the compounds are illustrated, anasterisk (*) indicates the point of attachment of the partial structureto the rest of the molecule.

“Cycloalkyl” by itself or as part of another substituent refers to apartially saturated or unsaturated cyclic alkyl radical. Where aspecific level of saturation is intended, the nomenclature“cycloalkanyl” or “cycloalkenyl” is used. Examples of cycloalkyl groupsinclude, but are not limited to, groups derived from cyclopropane,cyclobutane, cyclopentane, cyclohexane, and the like. In certainembodiments, a cycloalkyl group is C₃₋₁₅ cycloalkyl, and in certainembodiments, C₅₋₁₂ cycloalkyl, or C₃₋₇ cycloalkyl. In certainembodiments, a cycloalkyl is cyclohexyl.

“Cycloalkoxy” by itself or as part of another substituent refers to apartially saturated or unsaturated cyclic alkoxy radical. Examples ofcycloalkoxy groups include, but are not limited to, groups derived fromcyclopropoxy, cyclobutoxy, cyclopentyloxy, cyclohexyloxy, and the like.In certain embodiments, a cycloalkoxy group is C₃₋₁₅ cycloalkyl, and incertain embodiments, C₅₋₁₂ cycloalkyl, or C₃₋₇ cycloalkoxy. In certainembodiments, a cycloalkoxy is cyclohexyloxy.

“Disease” refers to a disease, disorder, condition, symptom, orindication.

“Diastereomeric purity” refers to the percent of one diastereomer of acompound relative to all other diastereomers of the compound in acomposition containing more than one diastereomer of the compound. Forexample, a composition has a diastereomeric purity of 97% of the(1S)-stereoisomer of a compound of Formula (I) when about 97% of thecompound of Formula (I) in the composition is the (1S)-stereoisomer andabout 3% of the compound of Formula (I) in the composition comprises oneor more of the other stereoisomers. In certain embodiments, thediastereomeric purity is, for example, greater than or at least 90%, atleast about 91%, at least about 92%, at least about 93%, at least about94%, at least about 95%, at least about 96%, at least about 97%, atleast about 98%, or at least about 99%.

“Halogen” refers to a fluoro, chloro, bromo, or iodo group.

“Parent aromatic ring system” refers to an unsaturated cyclic orpolycyclic ring system having a conjugated π (pi) electron system.Included within the definition of “parent aromatic ring system” arefused ring systems in which one or more of the rings are aromatic andone or more of the rings are saturated or unsaturated, such as, forexample, fluorene, indane, indene, phenalene, etc. Examples of parentaromatic ring systems include, but are not limited to, aceanthrylene,acenaphthylene, acephenanthrylene, anthracene, azulene, benzene,chrysene, coronene, fluoranthene, fluorene, hexacene, hexaphene,hexylene, as-indacene, s-indacene, indane, indene, naphthalene,octacene, octaphene, octalene, ovalene, penta-2,4-diene, pentacene,pentalene, pentaphene, perylene, phenalene, phenanthrene, picene,pleiadene, pyrene, pyranthrene, rubicene, triphenylene, trinaphthalene,and the like.

“Parkinson's disease” is a clinical syndrome comprising bradykinesia(slowness and poverty of movement), muscular rigidity, resting tremor(which usually abates during voluntary movement), and an impairment ofpostural balance leading to disturbance of gait and falling. Othersymptoms include gait and posture disturbances such as shuffling,decreased arm swing, turning “en bloc,” stooped, forward-reflexedposture, festination, gait freezing and dystonia; speech and swallowingdisturbances such as hypophonia, festinating speech, drooling, non-motorcauses of speech/language disturbance in both expressive and receptivelanguage, and dysphagia; as well as fatigue, masked facies,micrographia, impaired fine motor dexterity and coordination, impairedgross motor coordination, and poverty of movement. Non-motor mooddisturbances associated with Parkinson's disease include mooddisturbances such as depression; cognitive disturbances such as slowedreaction time, executive dysfunction, dementia, memory loss, andmedication effects; sleep disturbances such as excessive daytimesomnolence, insomnia, and disturbances in REM sleep; sensationdisturbances such as impair visual perception, dizziness and fainting,impaired proprioception, reduction or loss of sense of smell, and pain;and autonomic disturbances such as oily skin and seborrheic dermatitis,urinary incontinence, constipation and gastric dysmotility, alteredsexual function, and weight loss.

The Unified Parkinson's disease Rating scale is the primary clinicaltool used for the diagnosis of Parkinson's disease (see e.g., Gelb etal., Arch Neurol 1999, 56(1), 33-9; and Goetz, Mov Disord 2003, 18(7),738-50).

“Pharmaceutically acceptable salt” refers to a salt of a compound, whichpossesses the desired pharmacological activity of the parent compound.Such salts include: (1) acid addition salts, formed with inorganic acidssuch as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid,phosphoric acid, and the like; or formed with organic acids such asacetic acid, propionic acid, hexanoic acid, cyclopentanepropionic acid,glycolic acid, pyruvic acid, lactic acid, malonic acid, succinic acid,malic acid, maleic acid, fumaric acid, tartaric acid, citric acid,benzoic acid, 3-(4-hydroxybenzoyl)benzoic acid, cinnamic acid, mandelicacid, methanesulfonic acid, ethanesulfonic acid, 1,2-ethane-disulfonicacid, 2-hydroxyethanesulfonic acid, benzenesulfonic acid,4-chlorobenzenesulfonic acid, 2-naphthalenesulfonic acid,4-toluenesulfonic acid, camphorsulfonic acid,4-methylbicyclo[2.2.2]-oct-2-ene-1-carboxylic acid, glucoheptonic acid,3-phenylpropionic acid, trimethylacetic acid, tertiary butylacetic acid,lauryl sulfuric acid, gluconic acid, glutamic acid, hydroxynaphthoicacid, salicylic acid, stearic acid, muconic acid, and the like; and (2)salts formed when an acidic proton present in the parent compound isreplaced by a metal ion, e.g., an alkali metal ion, an alkaline earthion, or an aluminum ion; or coordinates with an organic base such asethanolamine, diethanolamine, triethanolamine, N-methylglucamine, andthe like.

“Patient” includes mammals, such as for example, humans.

“Pharmaceutical composition” refers to a composition comprising at leastone compound provided by the present disclosure and at least onepharmaceutically acceptable vehicle with which the compound isadministered to a patient.

“Pharmaceutically acceptable” refers to approved or approvable by aregulatory agency of a federal or a state government, listed in the U.S.Pharmacopeia, or listed in other generally recognized pharmacopeia foruse in mammals, including humans.

“Pharmaceutically acceptable vehicle” refers to a pharmaceuticallyacceptable diluent, a pharmaceutically acceptable adjuvant, apharmaceutically acceptable excipient, a pharmaceutically acceptablecarrier, or a combination of any of the foregoing with which a compoundof the present disclosure can be administered to a patient and whichdoes not destroy the pharmacological activity thereof and which isnontoxic when administered in doses sufficient to provide atherapeutically effective amount of the compound.

“Prodrug” refers to a derivative of a drug molecule that requires atransformation within the body to release the active drug. Prodrugs arefrequently, although not necessarily, pharmacologically inactive untilconverted to the parent drug. For example, a compound of Formula (I) isa prodrug of the drug, levodopa, or an active metabolite of the compoundof Formula (I), which exhibits therapeutic efficacy.

“Promoiety” refers to a group bonded to a drug, typically to afunctional group of the drug, via bond(s) that are cleavable underspecified conditions of use. The bond(s) between the drug and promoietymay be cleaved by enzymatic or non-enzymatic means. Under the conditionsof use, for example following administration to a patient, the bond(s)between the drug and promoiety may be cleaved to release the parentdrug. The cleavage of the promoiety may proceed spontaneously, such asvia a hydrolysis reaction, or may be catalyzed or induced by anotheragent, such as by an enzyme, by light, by acid, or by a change of orexposure to a physical or environmental parameter, such as a change oftemperature, pH, etc. The agent may be endogenous to the conditions ofuse, such as an enzyme present in the systemic circulation to which theprodrug is administered or the acidic conditions of the stomach, or theagent may be supplied exogenously. In certain embodiments, the drug islevodopa and a promoiety has the structure:

where R¹, R², R³, R⁴, and R⁵ are defined herein.

“Protecting group” refers to a grouping of atoms that when attached to areactive functional group in a molecule masks, reduces or preventsreactivity of the functional group. Examples of protecting groups can befound, for example in Wuts and Greene, “Protective Groups in OrganicSynthesis,” John Wiley & Sons, 4th ed. 2006; Harrison et al.,“Compendium of Organic Synthetic Methods,” Vols. 1-11, John Wiley & Sons1971-2003; Larock “Comprehensive Organic Transformations,” John Wiley &Sons, 2nd ed. 2000; and Paquette, “Encyclopedia of Reagents for OrganicSynthesis,” John Wiley & Sons, 11th ed. 2003. Examples of aminoprotecting groups include, but are not limited to, formyl, acetyl,trifluoroacetyl, benzyl, benzyloxycarbonyl (Cbz), tert-butoxycarbonyl(Boc), trimethylsilyl (TMS), 2-(trimethylsilyl)ethanesulfonyl (SES),trityl and substituted trityl groups, allyloxycarbonyl,9-fluorenylmethoxycarbonyl (FMOC), 6-nitroveratryloxycarbonyl (NVOC),and the like. Examples of hydroxy protecting groups include, but are notlimited to, those where the hydroxy group is either acylated oralkylated such as benzyl, and trityl ethers as well as alkyl ethers,tetrahydropyranyl ethers, trialkylsilyl ethers, and allyl ethers.

“Solvate” refers to a molecular complex of a compound with one or moresolvent molecules in a stoichiometric or non-stoichiometric amount. Suchsolvent molecules are those commonly used in the pharmaceutical art,which are known to be innocuous to a recipient, e.g., water, ethanol,and the like. A molecular complex of a compound or moiety of a compoundand a solvent can be stabilized by non-covalent intra-molecular forcessuch as, for example, electrostatic forces, van der Waals forces, orhydrogen bonds. The term “hydrate” refers to a complex where the one ormore solvent molecules are water including monohydrates andhemi-hydrates.

“Substantially one diastereomer” refers to a compound containing two ormore stereogenic centers such that the diastereomeric excess (d.e.) ofthe compound is greater than or about at least 90%. In certainembodiments, the d.e. is, for example, greater than or at least about91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%,about 98%, or about 99%.

“Substituted” refers to a group in which one or more hydrogen atoms areindependently replaced with the same or different substituent(s). Incertain embodiments, each substituent group can independently beselected from halogen, —NO₂, —OH, ═O, —COOH, —NH₂, —CN, —CF₃, —OCF₃,C₁₋₈ alkyl, substituted C₁₋₈ alkyl, C₁₋₈ alkoxy, and substituted C₁₋₈alkoxy In certain embodiments, each substituent group can independentlybe selected from halogen, —OH, —COOH, —CN, —CF₃, ═O, —NO₂, C₁₋₃ alkoxy,C₁₋₃ alkyl, and —NR¹⁰ ₂ wherein each R¹⁰ is independently chosen fromhydrogen and C₁₋₃ alkyl.

“Sustained release” refers to release of a therapeutic or preventiveamount of a drug or an active metabolite thereof over a period of timethat is longer than that of a conventional formulation of the drug. Fororal formulations, the term “sustained release” typically means releaseof the drug within the gastrointestinal tract lumen over a time periodranging from about 2 to about 30 hours, and in certain embodiments, overa time period ranging from about 4 to about 24 hours. Sustained releaseformulations achieve therapeutically effective concentrations of thedrug in the systemic circulation over a prolonged period of timerelative to that achieved by oral administration of a conventionalformulation of the drug. “Delayed release” refers to release of the drugor an active metabolite thereof into the gastrointestinal lumen after adelayed time period, for example a delay of about 1 to about 12 hours,relative to that achieved by oral administration of a conventionalformulation of the drug.

“Treating” or “treatment” of any disease or disorder refers to arrestingor ameliorating a disease, disorder, or at least one of the clinicalsymptoms of a disease or disorder, reducing the risk of acquiring adisease, disorder, or at least one of the clinical symptoms of a diseaseor disorder, reducing the development of a disease, disorder or at leastone of the clinical symptoms of the disease or disorder, or reducing therisk of developing a disease or disorder or at least one of the clinicalsymptoms of a disease or disorder. “Treating” or “treatment” also refersto inhibiting the disease or disorder, either physically, (e.g.,stabilization of a discernible symptom), physiologically, (e.g.,stabilization of a physical parameter), or both, and to inhibiting atleast one physical parameter which may or may not be discernible to thepatient. In certain embodiments, “treating” or “treatment” refers todelaying the onset of the disease or disorder or at least one or moresymptoms thereof in a patient which may be exposed to or predisposed toa disease or disorder even though that patient does not yet experienceor display symptoms of the disease or disorder.

“Therapeutically effective amount” refers to the amount of a compoundthat, when administered to a subject for treating a disease or disorder,or at least one of the clinical symptoms of a disease or disorder, issufficient to affect such treatment of the disease, disorder, orsymptom. The “therapeutically effective amount” can vary depending, forexample, on the compound, the disease, disorder, and/or symptoms of thedisease or disorder, severity of the disease, disorder, and/or symptomsof the disease or disorder, the age, weight, and/or health of thepatient to be treated, and the judgment of the prescribing physician. Anappropriate amount in any given instance can be readily ascertained bythose skilled in the art or capable of determination by routineexperimentation.

“Therapeutically effective dose” refers to a dose that provideseffective treatment of a disease or disorder in a patient. Atherapeutically effective dose can vary from compound to compound, andfrom patient to patient, and can depend upon factors such as thecondition of the patient and the route of delivery. A therapeuticallyeffective dose can be determined in accordance with routinepharmacological procedures known to those skilled in the art.

Compounds

In certain embodiments, a compound of the present disclosure is acompound of Formula (I):

stereoisomers thereof, pharmaceutically acceptable salts of any of theforegoing, or pharmaceutically acceptable solvates of any of theforegoing, wherein:

R¹ is chosen from C₁₋₈ alkyl, substituted C₁₋₈ alkyl, C₁₋₈ alkoxy,substituted C₁₋₈ alkoxy, C₃₋₇ cycloalkyl, substituted C₃₋₇ cycloalkyl,C₃₋₇ cycloalkoxy, substituted C₃₋₇ cycloalkoxy, phenyl, substitutedphenyl, phenyloxy, and substituted phenyloxy;

R² and R³ are independently chosen from C₁₋₈ alkyl, substituted C₁₋₈alkyl, C₁₋₈ alkoxy, substituted C₁₋₈ alkoxy, C₃₋₇ cycloalkyl, andsubstituted C₃₋₇ cycloalkyl; and R⁴ and R⁵ are independently chosen fromhydrogen, C₁₋₈ alkyl, and substituted C₁₋₈ alkyl;

wherein each substituent group is independently chosen from halogen,—OH, —COOH, —CN, —CF₃, ═O, —NO₂, C₁₋₃ alkoxy, C₁₋₃ alkyl, and —NR¹⁰ ₂wherein each R¹⁰ is independently chosen from hydrogen and C₁₋₃ alkyl.

In certain embodiments of a compound of Formula (I), R¹ is chosen fromC₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, and C₃₋₇cycloalkoxy; each of R² and R³ is independently chosen from C₁₋₅ alkyland C₁₋₅ alkoxy; and R⁴ and R⁵ are independently chosen from hydrogenand methyl.

In certain embodiments of a compound of Formula (I), R¹ is chosen fromC₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, and C₃₋₇cycloalkoxy; each of R² and R³ are chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; and R⁴ and R⁵ are independently chosen from hydrogen and methyl.

In certain embodiments of a compound of Formula (I), R¹ is chosen frommethyl, isopropyl, phenyl, cyclohexyl, methoxy, ethoxy, propoxy,isopropoxy, and cyclohexyloxy; each of R² and R³ is chosen from C₁₋₅alkyl and C₁₋₅ alkoxy; and R⁴ and R⁵ are independently chosen fromhydrogen and methyl.

In certain embodiments of a compound of Formula (I), R¹ is chosen fromC₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, and C₃₋₇cycloalkoxy; each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is C₁₋₃ alkyl; and R⁵ is hydrogen.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, andC₃₋₇ cycloalkoxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is C₁₋₃ alkyl, and R⁵ is hydrogen; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (S)-configuration and incertain embodiments the stereochemistry at the carbon atom to which R⁴is bonded is of the (R)-configuration.

In certain embodiments of a compound of Formula (I), R¹ is chosen fromC₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, and C₃₋₇cycloalkoxy; each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, andC₃₋₇ cycloalkoxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (S)-configuration and incertain embodiments the stereochemistry at the carbon atom to which R⁴is bonded is of the (R)-configuration.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, andC₃₋₇ cycloalkoxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the compound is chosen from:

-   (2R)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2R)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2R)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (2R)-2phenylcarbonyloxypropyl    (2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate; and-   (2S)-2phenylcarbonyloxypropyl    (2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I), R¹ is chosen fromC₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, and C₃₋₇cycloalkoxy; each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is C₁₋₃ alkyl.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, andC₃₋₇ cycloalkoxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is C₁₋₃ alkyl; the stereochemistry at thecarbon atom to which R⁵ is bonded is of the (S)-configuration and incertain embodiments, the stereochemistry at the carbon atom to which R⁵is bonded is of the (R)-configuration.

In certain embodiments of a compound of Formula (I), R¹ is chosen fromC₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, and C₃₋₇cycloalkoxy; each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, andC₃₋₇ cycloalkoxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁵ is bonded is of the (S)-configuration and incertain embodiments, the stereochemistry at the carbon atom to which R⁵is bonded is of the (R)-configuration.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, cyclohexyl, andcyclohexyloxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the compound is chosen from:

-   (2S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (2S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (2R)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2R)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2R)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (2R)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I), R¹ is chosen fromC₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, and C₃₋₇cycloalkoxy; each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; and each of R⁴ and R⁵ is independently C₁₋₃ alkyl.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, andC₃₋₇ cycloalkoxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, and each of R⁴ and R⁵ is independently C₁₋₃ alkyl; thestereochemistry at the carbon atom to which R⁴ is bonded is of the(S)-configuration, and the stereochemistry at the carbon atom to whichR⁵ is bonded is of the (S)-configuration.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, andC₃₋₇ cycloalkoxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, and each of R⁴ and R⁵ is independently C₁₋₃ alkyl; thestereochemistry at the carbon atom to which R⁴ is bonded is of the(S)-configuration, and the stereochemistry at the carbon atom to whichR⁵ is bonded is of the (R)-configuration.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, andC₃₋₇ cycloalkoxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, and each of R⁴ and R⁵ is independently C₁₋₃ alkyl; thestereochemistry at the carbon atom to which R⁴ is bonded is of the(R)-configuration, and the stereochemistry at the carbon atom to whichR⁵ is bonded is of the (S)-configuration.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, andC₃₋₇ cycloalkoxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, and each of R⁴ and R⁵ is independently C₁₋₃ alkyl; thestereochemistry at the carbon atom to which R⁴ is bonded is of the(R)-configuration, and the stereochemistry at the carbon atom to whichR⁵ is bonded is of the (R)-configuration.

In certain embodiments of a compound of Formula (I), R¹ is chosen fromC₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, and C₃₋₇cycloalkoxy; each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, andC₃₋₇ cycloalkoxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (S)-configuration, and thestereochemistry at the carbon atom to which R⁵ is bonded is of the(S)-configuration.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, andC₃₋₇ cycloalkoxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (S)-configuration, and thestereochemistry at the carbon atom to which R⁵ is bonded is of the(R)-configuration.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, andC₃₋₇ cycloalkoxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (R)-configuration, and thestereochemistry at the carbon atom to which R⁵ is bonded is of the(S)-configuration.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, andC₃₋₇ cycloalkoxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (R)-configuration, and thestereochemistry at the carbon atom to which R⁵ is bonded is of the(R)-configuration.

In certain embodiments of a compound of Formula (I) wherein R¹ is chosenfrom C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, andC₃₋₇ cycloalkoxy, each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the compound is chosen from:

-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S,2R)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2R)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2R)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S,2R)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1R,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1R,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1R,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1R,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1R,2R)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1R,2R)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1R,2R)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1R,2R)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I), R⁴ is methyl and R⁵is hydrogen.

In certain embodiments of a compound of Formula (I), R¹ is methyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen. In certain embodiments of a compound of Formula (I)wherein R¹ is methyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pivolyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methyl ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methyl ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-hexanoyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-isopropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ismethyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is hydrogen, the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (R)-isomer of any of the immediately preceding compounds. Forexample, the (R)-isomers of the immediately preceding compounds ofFormula (I) are:

-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pivolyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methyl ethyl    (2S)-2-amino-3-[3,4-bis(2-hexanoyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methyl ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-isopropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I), R¹ is ethyl; R² andR³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl; and R⁵is hydrogen. In certain embodiments of a compound of Formula (I) whereinR⁴ is ethyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (S)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom:

-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-(3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propanoyloxyethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is ethyl,R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl,and R⁵ is hydrogen; the stereochemistry of the carbon atom to which R⁴is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (R)-isomer of any of the immediately preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is isopropyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen. In certain embodiments of a compound of Formula (I)wherein R¹ is isopropyl, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry ofthe carbon atom to which R⁴ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isisopropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is hydrogen; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (R)-isomer of any of the immediately preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is propyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen. In certain embodiments of a compound of Formula (I)wherein R¹ is propyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(butanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ispropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is hydrogen; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (R)-isomer of any of the immediately preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is1-methylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 1-methylpropyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry of the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is2-methylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 2-methylpropyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry of the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is tert-butyl;R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen.

In certain embodiments of a compound of Formula (I) wherein R¹ istert-butyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (S)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom:

-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ istert-butyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (R)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (R)-isomer of any of the immediately preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is1,1-dimethylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 1,1-dimethylpropyl, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry of the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,2-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,1-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is1,2-dimethylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 1,2-dimethylpropyl, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry of the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,2-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is2,2-dimethylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 2,2-dimethylpropyl, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry of the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3,3-dimethylbutanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2,2-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is butyl; R² andR³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl; and R⁵is hydrogen. In certain embodiments of a compound of Formula (I) whereinR¹ is butyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is hydrogen, the stereochemistry of the carbon atomto which R⁴ is bonded is of the (S)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom:

-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is butyl,R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl,and R⁵ is hydrogen; the stereochemistry of the carbon atom to which R⁴is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (R)-isomer of any of the immediately preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is1-methylbutyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 1-methylbutyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry of the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is2-methylbutyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 2-methylbutyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry of the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is3-methylbutyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 3-methylbutyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry of the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(4-methylpentanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is3-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is pentyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen. In certain embodiments of a compound of Formula (I)wherein R¹ is pentyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(hexanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ispentyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is hydrogen; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (R)-isomer of any of the immediately preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is phenyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen. In certain embodiments of a compound of Formula (I)wherein R¹ is phenyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration. Forexample, in certain embodiments, a compound of Formula (I) is chosenfrom:

-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isphenyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is hydrogen; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration. For example, in certainembodiments, a compound of Formula (I) is chosen from the (1R)-isomer ofany of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is cyclohexyl;R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen. In certain embodiments of a compound of Formula (I)wherein R¹ is cyclohexyl, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry atthe carbon atom to which R⁴ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexylcarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ iscyclohexyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at the carbon atomto which R⁴ is bonded is of the (R)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (1R)-isomer of any of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is methoxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen. In certain embodiments of a compound of Formula (I)wherein R¹ is methoxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry atthe carbon to which R⁴ is bonded is of the (S)-configuration. Forexample, in certain embodiments, a compound of Formula (I) is chosenfrom:

-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-(3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-methoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ismethoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is hydrogen; the stereochemistry at the carbon towhich R⁴ is bonded is of the (R)-configuration. For example, in certainembodiments, a compound of Formula (I) is chosen from the (1R)-isomer ofany of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is ethoxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen. In certain embodiments of a compound of Formula (I)wherein R¹ is ethoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (S)-configuration. Forexample, in certain embodiments a compound of Formula (I) is chosenfrom:

-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-(3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isethoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is hydrogen; the stereochemistry at the carbon atom towhich R⁴ is bonded is of the (R)-configuration. For example, in certainembodiments a compound of Formula (I) is chosen from the (1R)-isomer ofany of the preceding compounds

In certain embodiments of a compound of Formula (I), R¹ is isopropoxy;

R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen. In certain embodiments of a compound of Formula (I)wherein R¹ is isopropoxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry atthe carbon atom to which R⁴ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-(3,4-bis(isoproxycarbonyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isisopropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at the carbon atomto which R⁴ is bonded is of the (R)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (1R)-isomer of any of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is propoxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen. In certain embodiments of a compound of Formula (I)wherein R¹ is propoxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry atthe carbon atom to which R⁴ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-propoxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ispropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is hydrogen; the stereochemistry at the carbon atom towhich R⁴ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (1R)-isomer of any of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is1-methylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 1-methylpropoxy, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry at the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is2-methylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is isopropoxy, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry at the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylpropoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is1,1-dimethylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 1,1-dimethylpropoxy, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry at the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,1-dimethylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is1,2-dimethylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 1,2-dimethylpropoxy, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry at the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxylcarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,2-dimethylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is2,2-dimethylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 2,2-dimethylpropoxy, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry at the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methyl ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2,2-dimethylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is tert-butoxy;R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen. In certain embodiments of a compound of Formula (I)wherein R¹ is tert-butoxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry atthe carbon atom to which R⁴ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(tert-butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ istert-butoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at the carbon atomto which R⁴ is bonded is of the (R)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (1R)-isomer of any of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is butoxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen. In certain embodiments of a compound of Formula (I)wherein R¹ is butoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-(butoxycarbonyloxy)-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is hydrogen; the stereochemistry at the carbon atom towhich R⁴ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (1R)-isomer of any of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is1-methylbutoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 1-methylbutoxy, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry at the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(1-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is2-methylbutoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 2-methylbutoxy, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry at the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(2-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is3-methylbutoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is 3-methylbutoxy, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry at the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(3-methylbutoxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is3-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is pentyloxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen. In certain embodiments of a compound of Formula (I)wherein R¹ is pentyloxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry atthe carbon atom to which R⁴ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-(pentyloxycarbonyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ispentyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is hydrogen; the stereochemistry at the carbon atom towhich R⁴ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (1R)-isomer of any of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ iscyclohexyloxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is hydrogen. In certain embodiments of acompound of Formula (I) wherein R¹ is cyclohexyloxy, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ishydrogen; the stereochemistry at the carbon atom to which R⁴ is bondedis of the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-cyclohexyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ iscyclohexyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is phenyloxy;

R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is hydrogen. In certain embodiments of a compound of Formula (I)wherein R¹ is phenyloxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry atthe carbon atom to which R⁴ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-phenyloxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S)-1-methyl-2-phenyloxycarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isphenyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₁₅ alkoxy,R⁴ is methyl, and R⁵ is hydrogen; the stereochemistry at the carbon atomto which R⁴ is bonded is of the (R)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (1R)-isomer of any of the preceding compounds.

In certain embodiments of a compound of Formula (I), R⁴ is hydrogen andR⁵ is methyl.

In certain embodiments of a compound of Formula (I), R¹ is methyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is hydrogen;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is methyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁵ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl (2S)-2-amino-3-[3,4-bis(2,2-dimethyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ismethyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ishydrogen, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (2R)-isomer of any of the immediately preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is ethyl; R² andR³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is hydrogen; andR⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is ethyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁵ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl (2S)-2-amino-3-[3,4-bis(2,2-dimethyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is ethyl,R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ishydrogen, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (2R)-isomer of any of the immediately preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is isopropyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is hydrogen;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is isopropyl, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry ofthe carbon atom to which R⁵ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isisopropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is hydrogen, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (2R)-isomer of any of the immediately preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is propyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is hydrogen;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is propyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁵ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl (2S)-2-amino-3-[3,4-bis(2,2-dimethyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(butanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ispropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ishydrogen, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (2R)-isomer of any of the immediately preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is1-methylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1-methylpropyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is2-methylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 2-methylpropyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is tert-butyl;R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ ishydrogen; and R⁵ is methyl. In certain embodiments of a compound ofFormula (I) wherein R¹ is tert-butyl, R² and R³ are both chosen fromC₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ is methyl; thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate

(2S)-2-(tert-butylcarbonyloxy)propyl(2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;

-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butylcarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ istert-butyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁵ is bonded is of the (R)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (2R)-isomer of any of the immediately preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is1,1-dimethylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1,1-dimethylpropyl, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,1-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R) stereoisomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is1,2-dimethylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1,2-dimethylpropyl, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,2-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is2,2-dimethylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 2,2-dimethylpropyl, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3,3-dimethylbutanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2,2-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is butyl; R² andR³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is hydrogen; andR⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is butyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁵ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl (2S)-2-amino-3-[3,4-bis(2,2-dimethyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(pentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is butyl,R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ishydrogen, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (2R)-isomer of any of the immediately preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is1-methylbutyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1-methylbutyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate; and

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is2-methylbutyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 2-methylbutyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is3-methylbutyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 3-methylbutyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is3-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the immediatelypreceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is pentyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is hydrogen;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is pentyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁵ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl (2S)-2-amino-3-[3,4-bis(2,2-dimethyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(hexanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ispentyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ishydrogen, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (2R)-isomer of any of the immediately preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is phenyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is hydrogen;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is phenyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁵ is bonded is of the (S)-configuration. Forexample, in certain embodiments, a compound of Formula (I) is chosenfrom:

-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl (2S)-2-amino-3-[3,4-bis(2,2-dimethyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isphenyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ishydrogen, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (R)-configuration. For example, in certainembodiments, a compound of Formula (I) is chosen from the (2R)-isomer ofany of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is cyclohexyl;R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ ishydrogen; and R⁵ is methyl. In certain embodiments of a compound ofFormula (I) wherein R¹ is cyclohexyl, R² and R³ are both chosen fromC₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ is methyl; thestereochemistry at the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ iscyclohexyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at the carbon atomto which R⁵ is bonded is of the (R)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (2R)-isomer of any of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is methoxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is hydrogen;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is methoxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry atthe carbon to which R⁵ is bonded is of the (S)-configuration. Forexample, in certain embodiments, a compound of Formula (I) is chosenfrom:

-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl (2S)-2-amino-3-[3,4-bis(2,2-dimethyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-methoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ismethoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is hydrogen, and R⁵ is methyl; the stereochemistry at the carbon towhich R⁵ is bonded is of the (R)-configuration. For example, in certainembodiments, a compound of Formula (I) is chosen from the (2R)-isomer ofany of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is ethoxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is hydrogen;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is ethoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁵ is bonded is of the (S)-configuration. Forexample, in certain embodiments a compound of Formula (I) is chosenfrom:

-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl (2S)-2-amino-3-[3,4-bis(2,2-dimethyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-ethoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isethoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ishydrogen, and R⁵ is methyl; the stereochemistry at the carbon atom towhich R⁵ is bonded is of the (R)-configuration. For example, in certainembodiments a compound of Formula (I) is chosen from the (2R)-isomer ofany of the preceding compounds

In certain embodiments of a compound of Formula (I), R¹ is isopropoxy;R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ ishydrogen; and R⁵ is methyl. In certain embodiments of a compound ofFormula (I) wherein R¹ is isopropoxy, R² and R³ are both chosen fromC₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ is methyl; thestereochemistry at the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-isopropoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isisopropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at the carbon atomto which R⁵ is bonded is of the (R)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (2R)-isomer of any of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is propoxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is hydrogen;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is propoxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry atthe carbon atom to which R⁵ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl (2S)-2-amino-3-[3,4-bis(2,2-dimethyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ispropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is hydrogen, and R⁵ is methyl; the stereochemistry at the carbon atom towhich R⁵ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (2R)-isomer of any of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is1-methylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1-methylpropoxy, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry at the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is2-methylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 2-methylpropoxy, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry at the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is1,1-dimethylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1,1-dimethylpropoxy, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry at the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,1-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,1-dimethylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is1,2-dimethylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1,2-dimethylpropoxy, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry at the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,2-dimethylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is2,2-dimethylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 2,2-dimethylpropoxy, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry at the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2,2-dimethylpropoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2,2-dimethylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is tert-butoxy;R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ ishydrogen; and R⁵ is methyl. In certain embodiments of a compound ofFormula (I) wherein R¹ is tert-butoxy, R² and R³ are both chosen fromC₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ is methyl; thestereochemistry at the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(tert-butoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ istert-butoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at the carbon atomto which R⁵ is bonded is of the (R)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (2R)-isomer of any of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is butoxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is hydrogen;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is butoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁵ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl (2S)-2-amino-3-[3,4-bis(2,2-dimethyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-butoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate; and

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ishydrogen, and R⁵ is methyl; the stereochemistry at the carbon atom towhich R⁵ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (2R)-isomer of any of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ is1-methylbutoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1-methylbutoxy, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry at the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(1-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is2-methylbutoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 2-methylbutoxy, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry at the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(2-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is3-methylbutoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 3-methylbutoxy, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,

R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at the carbon atomto which R⁵ is bonded is of the (S)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom:

-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-(3-methylbutoxy)carbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is3-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is pentyloxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is hydrogen;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is pentyloxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry atthe carbon atom to which R⁵ is bonded is of the (S)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from:

-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ispentyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is hydrogen, and R⁵ is methyl; the stereochemistry at the carbon atom towhich R⁵ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (2R)-isomer of any of the preceding compounds.

In certain embodiments of a compound of Formula (I), R¹ iscyclohexyloxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is hydrogen; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is cyclohexyloxy, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ ismethyl; the stereochemistry at the carbon atom to which R⁵ is bonded isof the (S)-configuration. For example, in certain embodiments of acompound of Formula (I), the compound is chosen from:

-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-cyclohexyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ iscyclohexyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is hydrogen, and R⁵ is methyl; the stereochemistry at thecarbon atom to which R⁵ is bonded is of the (R)-configuration. Forexample, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (2R)-isomer of any of the precedingcompounds.

In certain embodiments of a compound of Formula (I), R¹ is phenyloxy;

R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ ishydrogen; and R⁵ is methyl. In certain embodiments of a compound ofFormula (I) wherein R¹ is phenyloxy, R² and R³ are both chosen from C₁₋₅alkyl and C₁₋₅ alkoxy, R⁴ is hydrogen, and R⁵ is methyl; thestereochemistry at the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-dibutoxycarbonyloxyphenyl)propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (2S)-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isphenyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is hydrogen, and R⁵ is methyl; the stereochemistry at the carbon atom towhich R⁵ is bonded is of the (R)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen fromthe (2R)-isomer of any of the preceding compounds.

In certain embodiments of a compound of Formula (I), R⁴ is methyl and R⁵is methyl.

In certain embodiments of a compound of Formula (I), R¹ is methyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is methyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl (2S)-2-amino-3-[3,4-bis(2-methyl    propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-acetyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ismethyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (S)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1S,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ ismethyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (S)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2S)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ ismethyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is ethyl; R² andR³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl; and R⁵is methyl. In certain embodiments of a compound of Formula (I) whereinR¹ is ethyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is ethyl,R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl,and R⁵ is methyl; the stereochemistry of the carbon atom to which R⁴ isbonded is of the (S)-configuration and the stereochemistry of the carbonatom to which R⁵ is bonded is of the (R)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (1S,2R)-stereoisomer of any of the compounds in the precedinglist.

In certain embodiments of a compound of Formula (I) wherein R¹ is ethyl,R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl,and R⁵ is methyl; the stereochemistry of the carbon atom to which R⁴ isbonded is of the (R)-configuration and the stereochemistry of the carbonatom to which R⁵ is bonded is of the (S)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (1R,2S)-stereoisomer of any of the compounds in the precedinglist.

In certain embodiments of a compound of Formula (I) wherein R¹ is ethyl,R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl,and R⁵ is methyl; the stereochemistry of the carbon atom to which R⁴ isbonded is of the (R)-configuration and the stereochemistry of the carbonatom to which R⁵ is bonded is of the (R)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (1R,2R)-stereoisomer of any of the compounds in the precedinglist.

In certain embodiments of a compound of Formula (I), R¹ is isopropyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is isopropyl, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isisopropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (S)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1S,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ isisopropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (S)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2S)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ isisopropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is tert-butyl;R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is tert-butyl, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ istert-butyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ istert-butyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ istert-butyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is propyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is propyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ispropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (S)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1S,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ ispropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (S)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2S)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ ispropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is1-methylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1-methylpropyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl;the stereochemistry of the carbon atom to which R⁴ is bonded is of the(S)-configuration and the stereochemistry of the carbon atom to which R⁵is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is2-methylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 2-methylpropyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl;the stereochemistry of the carbon atom to which R⁴ is bonded is of the(S)-configuration and the stereochemistry of the carbon atom to which R⁵is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3-methylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is1,1-dimethylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹⁴ is 1,1-dimethylpropyl, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁴ is bonded isof the (S)-configuration and the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,1-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,1-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,1-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is1,2-dimethylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1,2-dimethylpropyl, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁴ is bonded isof the (S)-configuration and the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,2-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,2-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,2-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is2,2-dimethylpropyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 2,2-dimethylpropyl, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁴ is bonded isof the (S)-configuration and the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(3,3-dimethylbutanoyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2,2-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is2,2-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is2,2-dimethylpropyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is butyl; R² andR³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl; and R⁵is methyl. In certain embodiments of a compound of Formula (I) whereinR¹ is butyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentanoyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is butyl,R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl,and R⁵ is methyl; the stereochemistry of the carbon atom to which R⁴ isbonded is of the (S)-configuration and the stereochemistry of the carbonatom to which R⁵ is bonded is of the (R)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (1S,2R)-stereoisomer of any of the compounds in the precedinglist.

In certain embodiments of a compound of Formula (I) wherein R¹ is butyl,R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl,and R⁵ is methyl; the stereochemistry of the carbon atom to which R⁴ isbonded is of the (R)-configuration and the stereochemistry of the carbonatom to which R⁵ is bonded is of the (S)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (1R,2S)-stereoisomer of any of the compounds in the precedinglist.

In certain embodiments of a compound of Formula (I) wherein R¹ is butyl,R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl,and R⁵ is methyl; the stereochemistry of the carbon atom to which R⁴ isbonded is of the (R)-configuration and the stereochemistry of the carbonatom to which R⁵ is bonded is of the (R)-configuration. For example, incertain embodiments of a compound of Formula (I), the compound is chosenfrom the (1R,2R)-stereoisomer of any of the compounds in the precedinglist.

In certain embodiments of a compound of Formula (I), R¹ is1-methylbutyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1-methylbutyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl;the stereochemistry of the carbon atom to which R⁴ is bonded is of the(S)-configuration and the stereochemistry of the carbon atom to which R⁵is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is2-methylbutyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 2-methylbutyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl;the stereochemistry of the carbon atom to which R⁴ is bonded is of the(S)-configuration and the stereochemistry of the carbon atom to which R⁵is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is3-methylbutyl; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 3-methylbutyl, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl;the stereochemistry of the carbon atom to which R⁴ is bonded is of the(S)-configuration and the stereochemistry of the carbon atom to which R⁵is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(4-methylpentanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is3-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is3-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is3-methylbutyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is pentyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is pentyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-hexanoyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ispentyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (S)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1S,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ ispentyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (S)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2S)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ ispentyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is phenyl; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is phenyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isphenyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (S)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1S,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ isphenyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (S)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2S)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ isphenyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is cyclohexyl;R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is cyclohexyl, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexylcarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ iscyclohexyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ iscyclohexyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ iscyclohexyl, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is methoxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is methoxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-methoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ismethoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (S)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1S,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ ismethoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (S)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2S)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ ismethoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is ethoxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is ethoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-ethoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isethoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (S)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1S,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ isethoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (S)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2S)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ isethoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is isopropoxy;R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is isopropoxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isisopropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ isisopropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ isisopropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is tert-butoxy;

R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is tert-butoxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-tert-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ istert-butoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ istert-butoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ istert-butoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy,R⁴ is methyl, and R⁵ is methyl; the stereochemistry of the carbon atomto which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is propoxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is propoxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-propoxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ispropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (S)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1S,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ ispropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (S)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2S)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ ispropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is1-methylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1-methylpropoxy, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁴ is bonded isof the (S)-configuration and the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is2-methylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 2-methylpropoxy, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁴ is bonded isof the (S)-configuration and the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylpropoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is1,1-dimethylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1,1-dimethylpropoxy, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁴ is bonded isof the (S)-configuration and the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;    (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,1-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,1-dimethylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,1-dimethylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,1-dimethylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, R⁵ is methyl; the stereochemistry of the carbonatom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is1,2-dimethylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1,2-dimethylpropoxy, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁴ is bonded isof the (S)-configuration and the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,2-dimethylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,2-dimethylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl, the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1,2-dimethylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl, the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is2,2-dimethylpropoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 2,2-dimethylpropoxy, R² and R³ areboth chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ ismethyl; the stereochemistry of the carbon atom to which R⁴ is bonded isof the (S)-configuration and the stereochemistry of the carbon atom towhich R⁵ is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(1,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-(2,2-dimethylpropoxycarbonyloxy)-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2,2-dimethylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is2,2-dimethylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R¹ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is2,2-dimethylpropoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is butoxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is butoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-butoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (S)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1S,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ isbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (S)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2S)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ isbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ ismethyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is1-methylbutoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 1-methylbutoxy, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl;the stereochemistry of the carbon atom to which R⁴ is bonded is of the(S)-configuration and the stereochemistry of the carbon atom to which R⁵is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(1-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is1-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is2-methylbutoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 2-methylbutoxy, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl;the stereochemistry of the carbon atom to which R⁴ is bonded is of the(S)-configuration and the stereochemistry of the carbon atom to which R⁵is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(2-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is2-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is3-methylbutoxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is 3-methylbutoxy, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl;the stereochemistry of the carbon atom to which R⁴ is bonded is of the(S)-configuration and the stereochemistry of the carbon atom to which R⁵is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-(3-methylbutoxycarbonyloxy)propyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ is3-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is3-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ is3-methylbutoxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is pentyloxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is pentyloxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ ispentyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (S)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1S,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ ispentyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (S)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2S)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ ispentyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I), R¹ iscyclohexyloxy; R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy; R⁴ is methyl; and R⁵ is methyl. In certain embodiments of acompound of Formula (I) wherein R¹ is cyclohexyloxy, R² and R³ are bothchosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl;the stereochemistry of the carbon atom to which R⁴ is bonded is of the(S)-configuration and the stereochemistry of the carbon atom to which R⁵is bonded is of the (S)-configuration. For example, in certainembodiments of a compound of Formula (I), the compound is chosen from:

-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-2-cyclohexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ iscyclohexyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1S,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ iscyclohexyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2S)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ iscyclohexyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (R)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(R)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from the (1R,2R)-stereoisomer of anyof the compounds in the preceding list.

In certain embodiments of a compound of Formula (I), R¹ is phenyloxy; R²and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is methyl;and R⁵ is methyl. In certain embodiments of a compound of Formula (I)wherein R¹ is phenyloxy, R² and R³ are both chosen from C₁₋₅ alkyl andC₁₋₅ alkoxy, R⁴ is methyl, and R⁵ is methyl; the stereochemistry of thecarbon atom to which R⁴ is bonded is of the (S)-configuration and thestereochemistry of the carbon atom to which R⁵ is bonded is of the(S)-configuration. For example, in certain embodiments of a compound ofFormula (I), the compound is chosen from:

-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(acetyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethyl propanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3,3-dimethylbutanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(4-methylpentanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(hexanoyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-(3,4-bis(methoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-(3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(tert-butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(propoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,1-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(butoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(1-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(2-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(3-methylbutoxycarbonyloxy)phenyl]propanoate;-   (1S,2S)-1-methyl-2-phenyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(pentyloxycarbonyloxy)phenyl]propanoate;

pharmaceutically acceptable salts of any of the foregoing, andpharmaceutically acceptable solvates of any of the foregoing.

In certain embodiments of a compound of Formula (I) wherein R¹ isphenyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (S)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1S,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ isphenyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (S)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2S)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I) wherein R¹ isphenyloxy, R² and R³ are both chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy, R⁴is methyl, and R⁵ is methyl; the stereochemistry of the carbon atom towhich R⁴ is bonded is of the (R)-configuration and the stereochemistryof the carbon atom to which R⁵ is bonded is of the (R)-configuration.For example, in certain embodiments of a compound of Formula (I), thecompound is chosen from the (1R,2R)-stereoisomer of any of the compoundsin the preceding list.

In certain embodiments of a compound of Formula (I), the compound ischosen from:

-   (1R)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate    hydrochloride;-   (1R)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate hydrogen    fumarate;-   (1R)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(methylethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R)-2-ethoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R)-2-isopropoxycarbonyloxy-1-methylethyl    (2S)-2-amino-3-(3,4-bis(isopropoxycarbonyloxy)phenyl)propanoate    hydrochloride;-   (1R)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(isobutanoyloxy)phenyl]propanoate    hydrochloride;-   (1R)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate    hydrochloride;-   (1R,2R)-2-acetoxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R,2R)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R,2R)-2-isobutoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R,2R)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R,2R)-1-methyl-2-pentyloxycarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R,2R)-2-hexyloxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R,2R)-2-acetoxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R,2R)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (2R)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (2R)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(methylethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (2R)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride; and-   (2R)-2-phenylcarbonyloxypropyl    (2S)-2-amino-3-(3,4-bis(methylethoxycarbonyloxy)phenyl]propanoate    hydrochloride.

In certain embodiments of a compound of Formula (I), the compound ischosen from:

-   (1R)-1-methyl-2-phenylcarbonyloxyethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R,2R)-2-acetoxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R,2R)-1-methyl-2-(2-methylpropanoyloxy)propyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R,2R)-2-isopropoxycarbonyloxy-1-methylpropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (2R)-2-acetyloxypropyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride;-   (1R)-2-acetyloxy-1-methylethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate hydrogen    fumarate; and-   (1R)-1-methyl-2-(2-methylpropanoyloxy)ethyl    (2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate    hydrochloride.

In certain embodiments of a compound of Formula (I), the compound is asalt chosen from the hydrochloride salt and the fumarate salt.

Synthesis

Synthesis of catechol protected levodopa diester prodrugs of Formula (I)is disclosed in Xiang et al., U.S. Application Publication No.2005/0282891, which is incorporated by reference herein in its entirety:

Embodiments of compounds of Formula (I) may be prepared by methods wellknown in the art. In certain embodiments compounds of Formula (I) may beprepared from readily available starting materials using the followinggeneral methods and procedures. It will be appreciated that wheretypical or preferred process conditions (i.e., reaction temperatures,times, mole ratios of reactants, solvents, pressures) are given, otherprocess conditions can also be used unless otherwise stated. Optimumreaction conditions can vary with the particular reactants or solventused and may be determined by one skilled in the art by routineoptimization procedures. Additionally, as will be apparent to thoseskilled in the art, conventional protecting groups can be used toprevent certain functional groups from undergoing undesired reactions.Suitable protecting groups for various functional groups as well assuitable conditions for protecting and deprotecting particularfunctional groups are well known in the art. Furthermore, in certainembodiments, compounds of Formula (I) may contain one or more chiralcenters. Accordingly, such compounds can be prepared or isolated as purestereoisomers, i.e., as individual enantiomers or diastereomers, or asstereoisomer-enriched mixtures. All such stereoisomers (and enrichedmixtures) are included within the scope of the embodiments, unlessotherwise indicated. Pure stereoisomers (or enriched mixtures) can beprepared using, for example, optically active starting materials orstereoselective reagents well known in the art. Alternatively, racemicmixtures of such compounds can be separated using, for example, chiralcolumn chromatography, chiral resolving agents and the like.

In certain embodiments, compounds of Formula (I) may be prepared bymethods well known in the art (see e.g., Wuts and Greene, “ProtectiveGroups in Organic Synthesis,” John Wiley & Sons, 4th ed. 2006; Harrisonet al., “Compendium of Organic Synthetic Methods,” Vols. 1-11, JohnWiley & Sons 1971-2003; Larock “Comprehensive Organic Transformations,”John Wiley & Sons, 2nd ed. 2000; and Paquette, “Encyclopedia of Reagentsfor Organic Synthesis,” John Wiley & Sons, 11th ed. 2003).

Examples of useful preparative methods can be found in Gallop et al.U.S. Pat. No. 7,144,877, which is incorporated by reference herein inits entirety.

Compounds of Formula (I) may be prepared, for example, by reacting anon-catechol protected levodopa derivative with an acid chloride toprovide a catechol protected levodopa derivative and deprotecting theamine group to provide the corresponding catechol protected levodopadiester prodrug of Formula (I) (Scheme 1).

Intermediate (5) in Scheme 1 may be prepared from a diol (Scheme 1),from 2-hydroxyethyl halide (Scheme 2), or from ethylene dihalide (Scheme3). As shown in Scheme 1, a diol (1) is reacted with a silyl chloride toprovide the corresponding silyl ether (2), which is coupled withlevodopa to provide the corresponding silyl ether levodopa derivative(3). Reacting silyl ether levodopa derivative (3) with hydrogen fluorideaffords the corresponding alcohol (4). Coupling the alcohol with an acidunder appropriate conditions (e.g., DCC/DMAP or TEA) providesnon-catechol protected levodopa derivative intermediate (5), which canbe reacted with an acid chloride to provide catechol-protected levodopaderivative intermediate (6). Intermediate (6) can be deprotected toprovide compound (7) of Formula (I).

As illustrated in Scheme 2, non-catechol protected levodopa derivativeintermediate (5) may also be prepared by reacting a halide alcohol (8)with a carboxylic acid in an appropriate solvent such as TEA/DMAP/DCA toprovide the corresponding ester (9). Ester (9) can be reacted withBoc-protected levodopa to provide intermediate (5).

As illustrated in Scheme 3, non-catechol protected levodopa derivativeintermediate (5) may also be prepared by reacting dihalide (9) with acarboxylic acid to form the corresponding ester (10). Ester (10) can bereacted with N-Boc-protected levodopa to provide non-catechol protectedlevodopa derivative intermediate (5).

As illustrated in Scheme 1, compounds of Formula (I) may be prepared byreacting non-catechol protected levodopa derivative intermediate (5)with an acid chloride and deprotecting the amine group to provide thecorresponding catechol protected levodopa diester prodrug of Formula(I).

With appropriate manipulation and protection of the chemicalfunctionalities, synthesis of compounds of Formula (I) is accomplishedby methods analogous to those described above and in the experimentalsection.

Uses

Levodopa prodrugs of Formula (I) are precursors of dopamine. Thus,compounds of Formula (I) provided by the present disclosure may beadministered to a patient suffering from any disease or disorder forwhich the parent drug, levodopa, is known or hereafter discovered to betherapeutically effective. Compounds of Formula (I) may be administeredto a patient, such as a human, to treat a disease or disorder such asParkinson's disease. Methods comprise administering to a patient in needof such treatment a therapeutically effective amount of at least onecompound of Formula (I). In therapeutic methods provided by the presentdisclosure, a therapeutically effective amount of at least one compoundof Formula (I) may be administered to a patient suffering from a diseasesuch as Parkinson's disease, depression, attention deficit disorder,schizophrenia, manic depression, cognitive impairment disorders,restless legs syndrome, periodic limb movement disorders, tardivedyskinesia, Huntington's disease, Tourette's syndrome, hypertension,addictive disorders, stroke, congestive heart failure, excessive daytimesleepiness, dystonia, memory and learning deficits or loss, or Lewy Bodydisease. In certain embodiments, a therapeutically effective amount ofat least one compound of Formula (I) may be administered to a patientfor treating depression, attention deficit disorder, schizophrenia,manic depression, cognitive impairment disorders, restless legssyndrome, periodic limb movement disorders, tardive dyskinesia,Huntington's disease, Tourette's syndrome, hypertension, addictivedisorders, congestive heart failure, stroke, excessive daytimesleepiness, dystonia, and memory and learning deficit or loss.

In certain embodiments, compounds of Formula (I) or pharmaceuticalcompositions thereof may be co-administered with another therapeuticagent or drug, such as a decarboxylase inhibitor such as carbidopa orbenserazide, or a prodrug thereof, which may act as a protectant toinhibit or prevent premature decarboxylation of a compound of Formula(I) and/or the levodopa metabolite. Compounds of Formula (I) may bedelivered from the same dosage form as an L-aromatic amino aciddecarboxylase inhibitor or from a different dosage form. Compounds ofFormula (I) may be administered at the same time as, prior to, orsubsequent to, the administration of a decarboxylase inhibitor.Compounds of Formula (I) together with a decarboxylase inhibitor ordecarboxylase inhibitor prodrug or derivative may be administered to apatient, such as a human, to treat a disease or disorder such asParkinson's disease. Additionally, the therapeutic effectiveness of theabove combinations may be enhanced by co-administration of anotherpharmaceutically active agent such as a catechol-O-methyltransferase(COMT) inhibitor such as entacapone, an entacapone prodrug, tolecapone,and/or a tolecapone prodrug. Further, in certain embodiments, compoundsof Formula (I) or pharmaceutical compositions thereof may beadministered to a patient, such as a human, together with (i) adecarboxylase inhibitor such as carbidopa, a carbidopa prodrug,benserazide, or a benserazide prodrug, and (ii) a pharmaceuticallyactive agent such as a COMT inhibitor or prodrug thereof, to treat adisease or disorder such as Parkinson's disease.

Compounds of Formula (I) may be included in a pharmaceutical compositionand/or dosage form adapted for oral administration, although compoundsof Formula (I) may also be administered by any other convenient route,such as for example, by injection, infusion, inhalation, transdermal, orabsorption through epithelial or mucosal membranes (e.g., oral, rectal,and/or intestinal mucosa).

Compounds of Formula (I) or pharmaceutical compositions thereof mayprovide therapeutic or prophylactic plasma and/or blood concentrationsof levodopa following oral administration to a patient. Thepromoiety(ies) of compounds of Formula (I) may be cleaved in vivo eitherchemically and/or enzymatically to release the parent drug, levodopa.One or more enzymes present in the stomach, intestinal lumen, intestinaltissue, blood, liver, brain, or any other suitable tissue of a patientmay enzymatically cleave the promoiety of the administered compounds.For example, the carboxyl ester promoiety of compounds of Formula (I)may be cleaved after absorption from the gastrointestinal tract (e.g.,in intestinal tissue, blood, liver, or other suitable tissue of amammal). In certain embodiments, compounds of Formula (I) may beactively transported across the intestinal endothelium by activetransporters expressed throughout the gastrointestinal tract includingthe small intestine and colon. Levodopa may remain conjugated to thecarboxyl ester promoiety during transit across the intestinal mucosalbarrier to prevent or minimize presystemic metabolism. In certainembodiments, a compound of Formula (I) is essentially not metabolized tolevodopa within gastrointestinal enterocytes, but is metabolized tolevodopa within the systemic circulation, for example in the plasma. Insuch embodiments, compounds of Formula (I) may be absorbed into thesystemic circulation from the small and large intestines either byactive transport, passive diffusion, or by both active and passiveprocesses. The promoiety of a compound of Formula (I) may allow thecompound of Formula (I) to be absorbed into the systemic circulationeither by active transport, passive diffusion, or by both active andpassive processes.

Compounds of Formula (I) may be administered in similar amounts andusing a similar schedule as described in the art for levodopa. Forexample, compounds of Formula (I) may be useful in treating Parkinson'sdisease by administration of a compound of Formula (I) together with adecarboxylase inhibitor such as carbidopa or a prodrug of carbidopa, incertain embodiments by the oral route, to a mammalian subject in need ofthe treatment. In a human subject weighing about 70 kg, compounds ofFormula (I) may be administered at a dose over time having an equivalentweight of levodopa of from about 10 mg to about 10 g per day, and incertain embodiments, an equivalent weight of levodopa of from about 100mg to about 3 g per day. A dose of a compound of Formula (I) taken atany one time can have an equivalent weight of levodopa of from about 10mg to about 3 g. A dose may be adjusted by one skilled in the art basedon several factors, including, for example, the body weight and/orcondition of the subject treated, the dose of the decarboxylaseinhibitor or prodrug of a decarboxylase inhibitor being administered,the severity of the disease being treated, the incidence of sideeffects, the manner of administration, and the judgment of theprescribing physician. Doses and regimens may be determined by methodsknown to one skilled in the art.

Compounds of Formula (I) may be assayed in vitro and in vivo for thedesired therapeutic or prophylactic activity prior to use in humans. Forexample, in vitro assays may be used to determine whether administrationof a compound of Formula (I) is a substrate of a transporter protein,including organic cation transporters such as OCTN1 and OCTN2. Examplesof certain assay methods applicable to analyzing the ability ofcompounds of Formula (I) to act as a substrate for a transporter proteinare disclosed in Zerangue et al., U.S. Application Publication No.2003/0158254, which is incorporated by reference herein in its entirety.In vivo assays may also be used to determine whether administration of acompound of Formula (I) is therapeutically effective. Compounds ofFormula (I) may also be demonstrated to be effective and safe usinganimal model systems.

In certain embodiments, a therapeutically effective dose of a compoundof Formula (I) may provide therapeutic benefit without causingsubstantial toxicity. Toxicity of compounds of Formula (I) may bedetermined using standard pharmaceutical procedures and may beascertained by one skilled in the art. The dose ratio between toxic andtherapeutic effect is the therapeutic index. A dosage of a compound ofFormula (I) may be within a range capable of establishing andmaintaining a therapeutically effective circulating plasma and/or bloodconcentration of levodopa that exhibits little or no toxicity.

In addition to the use of compounds of Formula (I) and pharmaceuticalcompositions comprising compounds of Formula (I) provided by the presentdisclosure for treating Parkinson's disease, compounds of Formula (I)and compositions thereof may also be useful for treating otherdopamine-related diseases. Dopamine-related diseases can becharacterized by either insufficient or excessive functionaldopaminergic activity in the central nervous system. Examples of otherdopamine-related diseases include, but are not limited to, affectivedisorders such as depression and attention deficit disorder, psychoticdisorders such as schizophrenia and manic depression, cognitiveimpairment disorders such as mild cognitive impairment, movementdisorders such as restless legs syndrome, periodic limb movementdisorders, tardive dyskinesia, hypertension, Huntington's disease, andTourette's syndrome, addictive disorders such as alcohol addiction orabuse, nicotine addiction or abuse, and drug addiction and abuse,congestive heart failure, and excessive daytime sleepiness. For thetreatment of these and other dopamine-related diseases, compounds ofFormula (I) may be co-administered with an additional active agent suchas, for example, a decarboxylase inhibitor and/or a COMT inhibitor.Therapeutically effective doses for treating dopamine-related diseasesmay be determined by the methods disclosed herein for the treatment ofParkinson's disease and/or by methods known in the art.

Parkinson's Disease

Parkinson's disease (PD) is a progressive neurodegenerative disorderthat affects about 1% of the population over 55 years of age. Thepathological manifestation of PD is the loss of dopaminergic neurons inthe Substantia Nigra pars compacta and the presence of intracycloplasmicinclusions, called Lewy bodies, formed mainly by α-synuclein andubiquitin. The main symptoms of PD are tremor, bradykinesia,hypokinesia, and balance and coordination disturbances. Dopaminereplacement therapy can alleviate the symptoms of PD, however as thedisease progresses, drug-related side effects emerge as well asdisabling symptoms that are not responsive to the treatment. Althoughthe cause of PD is unknown, dopaminergic cell loss has been associatedwith several mechanisms of cell damage including excitotoxicity,disturbed calcium homeostasis, inflammation, apoptosis, distress energymetabolism, and protein aggregation. Because patients with PD have anormal lifespan, they must endure crippling symptoms for many years,severely impacting their quality of life. Therefore, a neuroprotectivetherapy that can stop or reduce the continual loss of dopaminergicneurons is needed.

Levodopa has been shown effective in treating vascular parkinsonism(Zijlmans et al., J Neurol Neurosurg Psychiatry 2004, 75, 545-547).

The efficacy of a compound of Formula (I) in treating Parkinson'sdisease may be assessed using animal models of Parkinson's disease andin clinical studies. Animal models of PD are known (see, e.g., O'Neil etal., CNS Drug Rev. 2005, 11(1), 77-96; Faulkner et al., Ann.Pharmacother. 2003, 37(2), 282-6; Olson et al., Am. J. Med. 1997,102(1), 60-6; Van Blercom et al., Clin Neuropharmacol. 2004, 27(3),124-8; Cho et al., Biochem. Biophys. Res. Commun. 2006, 341, 6-12;Emborg, J. Neuro. Meth. 2004, 139, 121-143; Tolwani et al., Lab Anim Sci1999, 49(4), 363-71; Hirsch et al., J Neural Transm Suppl 2003, 65,89-100; Orth and Tabrizi, Mov Disord 2003, 18(7), 729-37; and Betarbetet al., Bioessays 2002, 24(4), 308-18).

Schizophrenia

Schizophrenia includes a group of neuropsychiatric disorderscharacterized by dysfunctions of the thinking process, such asdelusions, hallucinations, and extensive withdrawal of the patient'sinterests from other people. Schizophrenia includes the subtypes ofparanoid schizophrenia characterized by a preoccupation with delusionsor auditory hallucinations, hebephrenic or disorganized schizophreniacharacterized by disorganized speech, disorganized behavior, and flat orinappropriate emotions; catatonic schizophrenia dominated by physicalsymptoms such as immobility, excessive motor activity, or the assumptionof bizarre postures; undifferentiated schizophrenia characterized by acombination of symptoms characteristic of the other subtypes; andresidual schizophrenia in which a person is not currently suffering frompositive symptoms but manifests negative and/or cognitive symptoms ofschizophrenia (see DSM-IV-TR classifications 295.30 (Paranoid Type),295.10 (Disorganized Type), 295.20 (Catatonic Type), 295.90(Undifferentiated Type), and 295.60 (Residual Type) (Diagnostic andStatistical Manual of Mental Disorders, 4^(th) Edition, AmericanPsychiatric Association, pp. 297-319, 2005). Schizophrenia includesthese and other closely associated psychotic disorders such asschizophreniform disorder, schizoaffective disorder, delusionaldisorder, brief psychotic disorder, shared psychotic disorder, psychoticdisorder due to a general medical condition, substance-induced psychoticdisorder, and unspecified psychotic disorders (DSM-IV-TR, 4^(th)Edition, pp. 297-344, American Psychiatric Association, 2005).Schizoaffective disorder characterized by symptoms of schizophrenia aswell as mood disorders such as major depression, bipolar mania, or mixedmania, is included as a subtype of schizophrenia.

Schizophrenia symptoms can be classified as positive, negative, orcognitive. Positive symptoms of schizophrenia include delusion andhallucination, which can be measured using, for example, the Positiveand Negative Syndrome Scale (PANSS); see Kay et al., SchizophreniaBulletin 1987, 13, 261-276). Negative symptoms of schizophrenia includeaffect blunting, anergia, alogia and social withdrawal, which can bemeasured for example, using (the Scales for the Assessment of NegativeSymptoms (SANS)(see Andreasen, 1983, Scales for the Assessment ofNegative Symptoms (SANS), Iowa City, Iowa). Cognitive symptoms ofschizophrenia include impairment in obtaining, organizing, and usingintellectual knowledge which can be measured using the Positive andNegative Syndrome Scale-cognitive subscale (PANSS-cognitive subscale)(Lindenmayer et al., J Nerv Ment Dis 1994, 182, 631-638) or by assessingthe ability to perform cognitive tasks such as, for example, using theWisconsin Card Sorting Test (see, e.g., Green et al., Am J Psychiatry1992, 149, 162-67; and Koren et al., Schizophr Bull 2006, 32(2),310-26).

Treating schizophrenia encompasses treating one or more symptoms,positive, negative, cognitive, and other associated features, ofschizophrenia. Examples of symptoms of schizophrenia include delusions,hallucinations, disorganized speech, affective flattening, alogia,anhedonia, inappropriate affect, dysphoric mood (in the form of, forexample, depression, anxiety, and/or anger), and some indications ofcognitive dysfunction.

Administration of high doses of a dopamine D2 receptor agonist orprecursor thereof such as levodopa, either alone or concomitant with anantipsychotic drug, has been shown to exacerbate psychosis, or eveninduce psychosis in non-psychotic patients (Lehrman and Sharar, J. MentHealth Admin, 1997, 24, 227-250; Yaryura-Tobias et al., Curr Ther ResClin Exp 1970, 12, 528-31; and Yaryura-Tobias et al., Dis Nerv Syst1970, 31, 60-63). However, relatively low doses of levodopa given asadjunctive treatment with typical antipsychotic drugs improves theclinical outcome in schizophrenia (see Jaskiw and Popli,Psychopharmacology 2004, 171, 365-374), suggesting an enhanced effect onnegative symptoms and cognitive impairment without worsening ofpsychotic symptoms (Alpert and Friedhoff, Am J Psychiatry 1980, 135,1329-32; Bruno and Bruno, Acta Psychiatr Scand, 1966, 42, 264-71;Buchanan et al., Aust N Z J Psychiatry 1975, 9, 269-71; Gerlach andLuhdorf, Psychopharmacologia 1975, 44, 105-110; Inanaga et al., FoliaPsychiatr Neurol Jpn 1975, 29, 123-43; and Kay and Opler, Int J PsychiatMed 1985-86, 15, 293-98). The results of these studies suggest thatadjunctive low-dose levodopa together with a low dose of a conventionalantipsychotic drug can be expected to generate a therapeutic profilesimilar to that of atypical antipsychotic drugs, including enhancedtreatment efficacy against negative symptoms and cognitive impairment inschizophrenia, with retained therapeutic effects on positive symptomsand without concomitant increased EPS liability. Because the severity ofcognitive impairment has a crucial impact on treatment outcome (Green,Am J Psychiatry 1996, 153, 321-330; and Harvey et al., Am J Psychiatry1998, 155, 1080-1086) the use of adjunctive, low-dose levodopa withselective dopamine D2 antagonists might also prove efficacious intreating both the positive and negative or cognitive symptoms ofschizophrenia (see also, Tran, U.S. application Ser. No. 11/855,641,which is incorporated by reference herein in its entirety).

Compounds of Formula (I) and pharmaceutical compositions thereof may beused to treat a positive symptom of schizophrenia, a negative orcognitive symptom of schizophrenia, both a positive and a negative orcognitive symptom of schizophrenia and/or closely associated psychoticdisorders such as schizophreniform disorder, schizoaffective disorder,delusional disorder, brief psychotic disorder, shared psychoticdisorder, psychotic disorder due to a general medical condition,substance-induced psychotic disorder, and/or unspecified psychoticdisorders in a patient (DSM-IV-TR, 4^(th) Edition, pp. 297-344, AmericanPsychiatric Association, 2005). Positive symptoms of schizophreniainclude delusion and hallucination. Negative symptoms of schizophreniainclude affect blunting, anergia, alogia, and social withdrawal.Cognitive symptoms of schizophrenia include impairment in obtaining,organizing, and using intellectual knowledge. In certain embodiments,compounds of Formula (I) and pharmaceutical compositions thereof may beused to treat both a positive and a negative or cognitive symptom ofschizophrenia by orally administering a compound of Formula (I) orpharmaceutical compositions thereof to a patient in need of suchtreatment.

The efficacy of compounds of Formula (I) and pharmaceutical compositionsthereof in treating schizophrenia may be determined by methods known tothose skilled in the art. For example, negative, positive, and/orcognitive symptom(s) of schizophrenia may be measured before and aftertreatment of the patient. Reduction in such symptom(s) indicates that apatient's condition has improved. Improvement in the symptoms ofschizophrenia may be assessed using, for example, the Scale forAssessment of Negative Symptoms (SANS), Positive and Negative SymptomsScale (PANSS) (see, e.g., Andreasen, 1983, Scales for the Assessment ofNegative Symptoms (SANS), Iowa City, Iowa; and Kay et al., SchizophreniaBulletin 1987, 13, 261-276), and using Cognitive Deficits tests such asthe Wisconsin Card Sorting Test (WCST) and other measures of cognitivefunction (see, e.g., Keshavan et al., Schizophr Res 2004, 70(2-3),187-194; Rush, Handbook of Psychiatric Measures, American PsychiatricPublishing 2000; Sajatovic and Ramirez, Rating Scales in Mental Health,2nd ed, Lexi-Comp, 2003; Keefe, et al., Schizophr Res. 2004, 68(2-3),283-97; and Keefe et al., Neuropsychopharmacology 2006, 31(9), 2033-46).

The efficacy of compounds of Formula (I) and pharmaceutical compositionsthereof may also be evaluated using animal models of schizophrenicdisorders (see e.g., Geyer and Moghaddam, in “Neuropsychopharmacology,”Davis et al., Ed., Chapter 50, pp. 689-701, American College ofNeuropsychopharmacology, 2002). For example, conditioned avoidanceresponse behavior (CAR) and catalepsy tests in rats are shown to beuseful in predicting antipsychotic activity and EPS effect liability,respectively (Wadenberg et al., Neuropsychopharmacology, 2001, 25,633-641).

Restless Legs Syndrome

Restless legs syndrome (RLS) afflicts between 5 and 10% of the generalpopulation. Although the clinical origin of RLS is unknown,characteristic symptoms of RLS include lower extremity dysesthesias orparesthesias, motor restlessness, nocturnal increase of paresthesias andmotor restlessness, and symptoms that increase at rest, i.e., sitting orlying. Typically, symptoms increase at night (Garcia-Borreguero et al.,Neurol. 2002, 11(2), 1573-79). RLS may start at any age, even duringchildhood, although is usually observed in adults. The clinical coursegenerally changes over time, but tends to become more pronounced withage, with up to 28% of those over 65 being affected (Clark, J. Am. Fam.Prac. 2001, 14(3), 368-374).

RLS is an intensely uncomfortable sensory-motor disorder. Besidessensory symptoms such as paresthesia, which is a sensation of numbness,tingling, burning or pain, accompanied by an urge to move the limbs,patients also experience motor symptoms. When awake and sitting or lyingdown, the patient has rhythmic or semi-rhythmic movements of the legs(i.e., dysesthesias). While sleeping, patients frequently demonstratesimilar semi-rhythmic legs movements, which have been referred to asperiodic leg movements during sleep (PLMS). These jerky leg movementsare repetitive, highly stereotypical and are characterized by extensionof the big toe along with flexion of the ankle, knee and sometimes thehip (i.e., a Babinski-like movement) (Clark, J. Am. Fam. Prac. 2001,14(3), 368-374). About 85-90% of RLS sufferers also exhibit PLMS andthese patients complain of daytime fatigue and sleepiness or insomnia,which have a profound negative effect on quality of life, includingdaytime fatigue, poor work performance and interrupted social and/orfamily life (National Institutes of Health, 2003 National SleepDisorders Research Plan, pp. 76-79).

The origin of RLS and PLMS is unknown and most cases are classified asidiopathic. Clinical and laboratory findings suggest that thedopaminergic neurotransmitter system may be involved. Defects in theopioid and serotonin systems may also play a role (Adler, Clin.Neuropharm. 1997, 20(2), 148-151). RLS is more prevalent in women thanmen and in individuals of Northern European ancestry. The inheritancepattern of RLS suggests an autosomal dominant mode of transmittance, butthe genes accounting for this observation are not known.

Certain patient populations exhibit RLS more frequently than does thegeneral population. In particular, iron deficiency has been associatedwith RLS, as have decreased levels of magnesium and folate. Dialysispatients, perhaps because of the prevalence of associated anemia, arefrequently afflicted, with 20% to 57% having symptoms of RLS. Inaddition, pregnant women often complain of RLS, although symptomsusually diminish or disappear after delivery.

Diagnostic criteria for RLS includes a distressing urge to move thelimbs because of paraesthesias or spontaneous jerks in the legs or lessoften in other body parts, a worsening of these symptoms at rest, atemporary relief by motor activity, and worsening of the symptoms in theevening or during the night (see e.g. Mathis, Swiss Med Wkly 2005, 135,687-96; and Allen et al., Sleep Med 2003, 4, 101-19).

Levodopa has been shown to be effective in treating RLS (Ondo andJankovic, Neurology 1996, 47, 1435-41; von Scheele, Lancet 1986,2(8504), 426-7; and Conti et al., Mot Disord 2007, 22(13), 1943-1951).

The efficacy of a compound of a levodopa prodrug in treating RLS may beassessed using animal models of RLS and in clinical studies.

Huntington's Disease

Huntington's disease is an autosomal dominant neurodegenerative disorderin which specific cell death occurs in the neostriatum and cortex(Martin, N Engl J Med 1999, 340, 1970-80). Onset usually occurs duringthe fourth or fifth decade of life, with a mean survival at age onset of14 to 20 years. Huntington's disease is universally fatal, and there isno effective treatment. Symptoms include a characteristic movementdisorder (Huntington's chorea), cognitive dysfunction, and psychiatricsymptoms. The disease is caused by a mutation encoding an abnormalexpansion of CAG-encoded polyglutamine repeats in the protein,huntingtin. A number of studies suggest that there is a progressiveimpairment of energy metabolism, possibly resulting from mitochondrialdamage caused by oxidative stress as a consequence of free radicalgeneration.

Levodopa has shown effectiveness in treating rigidity associated withHuntington's disease (see Bonelli and Wenning, Current PharmaceuticalDesign 2006, 12(21), 2701-2720).

The efficacy of a levodopa prodrug for treating Huntington's disease maybe assessed using animal models of Huntington's disease and clinicalstudies. Animal models of Huntington's disease are disclosed, forexample, in Riess and Hoersten, U.S. Application Publication No.2007/0044162; Rubinsztein, Trends in Genetics, 2002, 18(4), 202-209;Matthews et al., J. Neuroscience 1998, 18(1), 156-63; Tadros et al.,Pharmacol Biochem Behav 2005, 82(3), 574-82; and Kaddurah-Daouk et al.,U.S. Pat. No. 6,706,764 and U.S. Application Publication No.2007/0044162. An example of a placebo-controlled clinical trialevaluating the efficacy of a compound to treat Huntington's disease isdisclosed in Verbessem et al., Neurology 2003, 61, 925-230.

Dystonia

Dystonia is involuntary, slow, repetitive, sustained muscle contractionsthat may cause freezing in the middle of an action, as well as twistingor turning of the trunk, the entire body, or part of the body.

Dystonia is a neurological syndrome characterized by involuntary,patterned, sustained, or repetitive muscle contractions of opposingmuscles, causing twisting movements and abnormal postures. Causes ofdystonia include a severe lack of oxygen to the brain that occurs atbirth or later in life, Parkinson's disease, multiple sclerosis,toxicity due to accumulation of certain metals such as copper inWilson's disease, stroke, and as side effects to antipsychotic drugs.Chronic dystonia is usually genetic. Types and symptoms of dystoniainclude focal dystonias confined to particular muscles or muscle groupssuch as blepharospasm, oromandibular dystonia, spasmodic dysphonia,cervical dystonia, and task-specific dystonias, segmental dystonias inwhich certain parts of the body are affected, and generalized dystoniasin which muscles throughout the body are affected. Dopa-responsivedystonia, characterized by child hood onset, parkinsonian features, gaitand postural abnormalities, diurnal fluctuation, and autosomal dominantinheritance is a genetic disorder representing up to about 5% ofchildhood dystonias. Levodopa substantially improves or can completelyresolve this type of dystonia (Jankovic, Lancet Neurol 2006, 5, 864-72;and Schneider et al., Neurology 2006, 66(4), 599-601).

The efficacy of a compound of a levodopa prodrug in treating dystoniamay be assessed using animal models of dystonia and in clinical studies.

Tardive Dyskinesia

Tardive dyskinesia is a neurological disorder caused by the long-term orhigh-dose use of dopamine antagonists such as antipsychotics (Rascol andFabre, Clinical Neuropharmacology 2001, 24(6), 313-323). Tardivedyskinesia is characterized by repetitive, involuntary, purposelessmovements such as grimacing, tongue protrusion, lip smacking, puckeringand pursing of the lips, and rapid eye blinking, and can also involverapid movements of the arms, legs, and trunk.

Studies suggest that levodopa can be useful in treating movementdisorders induced by neuroleptic drugs such as tardive dyskinesia(Rascol and Fabre, Clinical Neuropharmacology 2001, 24(6), 313-323;Soares and McGrath, Schizophr Res 1999, 39(1), 1-16; and Ebadi andSmivasan, Pharmacological Reviews 1996, 47(4), 575-604),

Efficacy of tardive dyskinesia treatment can be assessed using animalmodels (Takeuchi et al., Prog Neuro-Psychopharmacol & Biol Psychiat1998, 22, 679-691; Abilio et al., Psychopharmacology 2002, 161, 340-347;Queiroz and Frussa-Filho, Prog Neuro-Psychopharmacol & Biol Psychiat1999, 23, 1405-1418; Andreassen et al., Br J Pharmacol 1996, 119(4),751-7; Dutra et al., Prog Neuro-Psychopharmacology & Biol Psychiatry2002, 26, 487-495; and Shoham, Brain Res 2004, 1004, 142-147), and inclinical trials.

Stroke

Levodopa combined with physiotherapy is shown to improve motor recoveryafter stroke (Scheidtmann et al., The Lancet, 2001, 358, 787-790; andFloel et al., Neurology 2005, 65(3), 472-4).

The efficacy of a compound of a levodopa prodrug in treating stroke maybe assessed using animal models of stroke and in clinical studies.

Learning and Memory Disorders and Deficits

Levodopa is shown to be effective in treating cognitive dysfunction inpatients with Parkinson's disease (Cools, Neuroscience Biobehavioral Rev2006, 30, 1-23; and Kulisevsky, Drugs Aging 2000, 16(5), 365-79),enhance training effects in motor memory formation in the elderly (Floelet al., Neurobiology of Aging 2006, PMID 17098331) and improve wordlearning in healthy patients (Knecht et al., Ann. Neurol 2004, 56(1),20-6).

The efficacy of a compound of a levodopa prodrug in treating learningand memory disorders may be assessed using animal models of learning andmemory disorders and in clinical studies.

Excessive Daytime Sleepiness

Excessive daytime sleepiness (EDS), also known as hypersomnia ischaracterized by recurrent episodes of excessive daytime sleepiness orprolonged nighttime sleep. Hypersomnia can be caused by genetics, braindamage, and disorders such as clinical depression and fibromyalgia andcan also be a symptom of other sleep disorders such as narcolepsy, sleepapnea, and restless legs syndrome. Hypersomnia can be diagnosed usingthe Epworth sleepiness test.

Levodopa has shown efficacy in treating hypersomnia (Silber, NeurologicClinics 2001, 19(1), 173-86; Paus et al., Movement Disorders 2003,18(6), 659-667; Hogl et al., Movement Disorders 2003, 18(3), 319-323;and O'Suilleabhain and Dewey, Arch Neurol 2002, 59, 986-989).

The efficacy of a compound of a levodopa prodrug in treating excessivedaytime sleepiness may be assessed using animal models of excessivedaytime sleepiness and in clinical studies.

Depression

Depressive disorders include major depressive disorder, dysthymicdisorder, premenstrual dysphoric disorder, minor depressive disorder,recurrent brief depressive disorder, and postpsychotic depressivedisorder of schizophrenia (see DSM IV).

The efficacy of compounds provided by the present disclosure fortreating depression can be evaluated in animal models of depression suchas the forced swim test (Porsolt et al., Nature 1977,266, 525-532; andPorsolt et al., Arch Int Pharmacodyn 1997,229, 327-336), the tailsuspension test (Cryan et al., Trends Pharmacol Sci 2002, 23, 238-245;and Cryan and Mombereau, Mol Psychiatr 2004, 9, 1050-1062), and well asother (Porsolt, Rev. Neurosci 2000,11, 53-58).

Pharmaceutical Compositions

Pharmaceutical compositions provided by the present disclosure maycomprise a therapeutically effective amount of a compound of Formula(I), and in certain embodiments, in purified form, together with asuitable amount of one or more pharmaceutically acceptable vehicles, soas to provide a composition for proper administration to a patient.Suitable pharmaceutical vehicles also include excipients such as starch,glucose, lactose, sucrose, gelatin, malt, rice, flour, chalk, silicagel, sodium stearate, glycerol monostearate, talc, sodium chloride,dried skim milk, glycerol, propylene, glycol, water, ethanol, and thelike. The present compositions may also contain wetting agents,emulsifying agents, and/or pH buffering agents. In addition, auxiliary,stabilizing, thickening, lubricating, and/or coloring agents may beused. In certain embodiments, pharmaceutical compositions may be in theform of a capsule. Other examples of suitable pharmaceutical vehiclesare described in the art.

Pharmaceutical compositions comprising a compound of Formula (I) may bemanufactured by means of conventional mixing, dissolving, granulating,dragee-making, levigating, emulsifying, encapsulating, entrapping, orlyophilizing processes. Pharmaceutical compositions may be formulated ina conventional manner using one or more physiologically acceptablecarriers, diluents, excipients, or auxiliaries, which facilitateprocessing of compounds of Formula (I) or crystalline form thereof andone or more pharmaceutically acceptable vehicles into formulations thatcan be used pharmaceutically. Proper formulation is dependent upon theroute of administration chosen. In certain embodiments, a pharmaceuticalcomposition comprising a compound of Formula (I) or crystalline formthereof may be formulated for oral administration, and in certainembodiments for sustained release oral administration. Pharmaceuticalcompositions provided by the present disclosure may take the form ofsolutions, suspensions, emulsion, tablets, pills, pellets, capsules,capsules containing liquids, powders, sustained-release formulations,suppositories, emulsions, aerosols, sprays, suspensions, or any otherform suitable for use.

In certain embodiments, a compound of Formula (I) may be incorporatedinto pharmaceutical compositions to be administered orally. Oraladministration of such pharmaceutical compositions may result in uptakeof a compound of Formula (I) throughout the intestine and entry into thesystemic circulation. Such compositions may be prepared in a mannerknown in the pharmaceutical art and comprise at least one compound ofFormula (I) and at least one pharmaceutically acceptable vehicle.Pharmaceutical compositions may include a therapeutically effectiveamount of at least one compound of Formula (I), in some embodiments, inpurified form, together with a decarboxylase inhibitor such ascarbidopa, a carbidopa prodrug, benserazide, or a benserazide prodrug,and a suitable amount of a pharmaceutically acceptable vehicle, so as toprovide an appropriate form for administration to a patient.

Compositions of the present disclosure may be obtained by conventionalprocedures using conventional pharmaceutical vehicles, well known in theart.

Pharmaceutical compositions for oral delivery may be in the form oftablets, lozenges, aqueous or oily suspensions, granules, powders,emulsions, capsules, syrups, or elixirs, for example. Orallyadministered pharmaceutical compositions may contain one or moreoptional agents, for example, sweetening agents such as fructose,aspartame or saccharin, flavoring agents such as peppermint, oil ofwintergreen, or cherry coloring agents and preserving agents, to providea pharmaceutically palatable preparation. Moreover, in tablet or pillforms, the pharmaceutical compositions may be coated to delaydisintegration and absorption in the gastrointestinal tract, therebyproviding a sustained action over an extended period of time.Selectively permeable membranes surrounding an osmotically activedriving compound are also suitable for orally administered compounds andpharmaceutical compositions. In these latter platforms, fluid from theenvironment surrounding the capsule is imbibed by the driving compound,which swells to displace the agent or agent composition through anaperture. These delivery platforms can provide an essentially zero orderdelivery profile as opposed to the spiked profiles of immediate releaseformulations. A time delay material such as glycerol monostearate orglycerol stearate may also be used. Oral pharmaceutical compositions mayinclude standard vehicles such as mannitol, lactose, starch, magnesiumstearate, sodium saccharine, cellulose, magnesium carbonate, etc. Suchvehicles may be of pharmaceutical grade.

For oral liquid preparations such as suspensions, elixirs and solutions,can include suitable carriers, excipients, or diluents include water,saline, alkylene glycols (e.g., propylene glycol), polyalkylene glycols(e.g., polyethylene glycol) oils, alcohols, slightly acidic buffers fromabout pH 4 to about pH 6 (e.g., acetate, citrate, ascorbate from about 5mM to about 50 mM), etc. Additionally, flavoring agents, preservatives,coloring agents, bile salts, acylcarnitines, and the like may be added.

Certain embodiments also include compositions that comprise, as theactive ingredient, at least one compound of Formula (I) associated withat least one pharmaceutically acceptable vehicle including excipients,carriers, diluents and/or adjuvants. In forming the compositions, acompound of Formula (I) may be mixed with an excipient, diluted by adiluent or enclosed within a carrier, which can be in the form of acapsule, sachet, paper or other container. When an excipient serves as adiluent, it can be a solid, semi-solid, or liquid material, which canact as a vehicle, carrier, or medium for a compound of Formula (I).Thus, compositions may be in the form of tablets, pills, powders,lozenges, sachets, cachets, elixirs, suspensions, emulsions, solutions,and syrups containing, for example, up to about 90% by weight of acompound of Formula (I) using, for example, soft and hard gelatincapsules.

In preparing a composition, it may be useful to mill a compound ofFormula (I) to provide an appropriate particle size prior to combiningwith other ingredients. The milled particle size of a compound ofFormula (I) may be adjusted depending on the aqueous solubility, and incertain embodiments, may be less than about 200 mesh and in certainembodiments, about 40 mesh. Examples of suitable excipients includelactose, dextrose, sucrose, sorbitol, mannitol, starches, gum acacia,calcium phosphate, alginates, tragacanth, gelatin, calcium silicate,microcrystalline cellulose, polyvinylpyrrolidone, cellulose, water,syrup, and methylcellulose. Compositions may additionally includelubricating agents such as talc, magnesium stearate, and mineral oil,wetting agents, emulsifying and suspending agents, preserving agentssuch as methyl- and propylhydroxy-benzoates, sweetening agents, pHadjusting and buffering agents, toxicity adjusting agents, flavoringagents, and the like. The compositions may be formulated so as toprovide quick, sustained, or delayed release of a compound of Formula(I) after administration to the patient by employing procedures known inthe art.

A composition may be formulated in unit dosage form, each dosage formcomprising an equivalent weight of levodopa ranging from about 1 mg toabout 1 g. Unit dosage form refers to a physically discrete unitsuitable as a unitary dosage for humans and other mammals, each unitcontaining a predetermined quantity of active material calculated toproduce an intended therapeutic effect, in association with a suitablepharmaceutical excipient, diluent, carrier and/or adjuvant.

Compounds of Formula (I) may be administered to a patient in atherapeutically effective amount. It will be understood, however, thatthe amount of a compound of Formula (I) actually administered will bedetermined by a physician, in the light of the relevant circumstances,including the condition to be treated, the chosen route ofadministration, the actual compound administered, the age, weight, andresponse of the individual patient, the disease being treated, theseverity of the patient's symptoms, and the like.

For preparing solid compositions such as tablets, a compound of Formula(I) may be mixed with a pharmaceutical excipient, diluent, carrierand/or adjuvant to form a solid pre-formulation composition containing ahomogeneous mixture containing a compound of Formula (I). When referringto these pre-formulation compositions as homogeneous, it is meant that acompound of Formula (I) is dispersed evenly throughout the compositionso that the composition can be readily subdivided into equally effectiveunit dosage forms such as tablets, pills, or capsules. This solidpre-formulation can then be subdivided into unit dosage forms of thetype described herein comprising, for example, an equivalent weight oflevodopa ranging from about 1 mg to about 1 g.

Tablets or pills comprising a compound of Formula (I) may be coated orotherwise compounded to provide a dosage form affording the advantage ofsustained release. For example, a tablet or pill may comprise an innerdosage and an outer dosage component, the latter being in the form of anenvelope over and/or enclosing the former. The two components may beseparated by an enteric layer. The enteric layer may serve to resistdisintegration in the stomach and permit the inner component to passintact into the duodenum, or to delay release. A variety of materialsmay be used for such enteric layers or coatings. For example, suchmaterials include a number of polymeric acids and mixtures of polymericacids with such materials as shellac, cetyl alcohol, or celluloseacetate.

Liquid dosage forms in which the compositions a compound of Formula (I)may be incorporated for oral administration or by injection includeaqueous solutions suitably flavored syrups, aqueous or oil suspensions,and flavored emulsions with edible oils such as cottonseed oil, sesameoil, coconut oil, or peanut oil, as well as elixirs and similarpharmaceutical vehicles.

In certain embodiments, a dosage form can be adapted to be administeredto a patient no more than twice per day, and in certain embodiments,only once per day. Dosing may be provided alone or in combination withother drugs and may continue as long as required for effective treatmentof the disease, disorder, or condition.

Pharmaceutical compositions comprising at least one compound of Formula(I) may be formulated for immediate release for parenteraladministration, oral administration, or by any other appropriate routeof administration.

Controlled drug delivery systems can be designed to deliver a drug insuch a way that the drug level is maintained within the therapeuticwindows and effective and safe blood levels are maintained for a periodas long as the system continues to deliver the drug at a particularrate. Controlled drug delivery can produce substantially constant bloodlevels of a drug as compared to fluctuations observed with immediaterelease dosage forms. For some drugs, maintaining a constant bloodstreamand tissue concentration throughout the course of therapy is the mostdesirable mode of treatment. Immediate release of these drugs can causeblood levels to peak above the level required to elicit the desiredresponse, which wastes the drug and may cause or exacerbate toxic sideeffects. Controlled drug delivery can result in optimum therapy, and notonly can reduce the frequency of dosing, but may also reduce theseverity of side effects. Examples of controlled release dosage formsinclude dissolution controlled systems, diffusion controlled systems,ion exchange resins, osmotically controlled systems, erodable matrixsystems, pH independent formulations, gastric retention systems, and thelike.

In certain embodiments, an oral dosage form of the present disclosurecan be a controlled release dosage form. Controlled deliverytechnologies can improve the absorption of a drug in a particular regionor regions of the gastrointestinal tract.

The appropriate oral dosage form for a particular pharmaceuticalcomposition of the present disclosure can depend, at least in part, onthe gastrointestinal absorption properties of the compound of Formula(I), the stability of the compound of Formula (I) in thegastrointestinal tract, the pharmacokinetics of the compound of Formula(I), and the intended therapeutic profile. An appropriate controlledrelease oral dosage form can be selected for a particular the compoundof Formula (I). For example, gastric retention oral dosage forms can beappropriate for compounds absorbed primarily from the uppergastrointestinal tract, and sustained release oral dosage forms can beappropriate for compounds absorbed primarily form the lowergastrointestinal tract.

Certain compounds are absorbed primarily from the small intestine. Ingeneral, compounds traverse the length of the small intestine in about 3to 5 hours. For compounds that are not easily absorbed by the smallintestine or that do not dissolve readily, the window for active agentabsorption in the small intestine may be too short to provide a desiredtherapeutic effect.

Gastric retention dosage forms, i.e., dosage forms that are designed tobe retained in the stomach for a prolonged period of time, can increasethe bioavailability of drugs that are most readily absorbed by the uppergastrointestinal tract. The residence time of a conventional dosage formin the stomach is about 1 to about 3 hours. After transiting thestomach, there is approximately a 3 to 5 hour window of bioavailabilitybefore the dosage form reaches the colon. However, if the dosage form isretained in the stomach, the drug can be released before it reaches thesmall intestine and will enter the intestine in solution in a state inwhich it can be more readily absorbed. Another use of gastric retentiondosage forms is to improve the bioavailability of a drug that isunstable to the basic conditions of the intestine (see, e.g., Hwang etal., Critical Reviews in Therapeutic Drug Carrier Systems, 1998,15,243-284).

To enhance drug absorption from the upper gastrointestinal tract,several gastric retention dosage forms have been developed. Examplesinclude, hydrogels (see, e.g., Gutierrez-Rocca et al., U.S. ApplicationPublication No. 2003/0008007), buoyant matrices (see, e.g., Lohray etal., Application Publication No. 2006/0013876), polymer sheets (see,e.g., Mohammad, Application Publication No. 2005/0249798), microcellularfoams (see, e.g., Clarke et al., Application Publication No.2005/0202090), and swellable dosage forms (see, e.g., Edgren et al.,U.S. Application Publication No. 2005/0019409; Edgren et al., U.S. Pat.No. 6,797,283; Jacob et al., U.S. Application Publication No.2006/0045865; Ayres, U.S. Application Publication No. 2004/0219186;Gusler et al., U.S. Pat. No. 6,723,340; Flashner-Barak et al., U.S. Pat.No. 6,476,006; Wong et al., U.S. Pat. Nos. 6,120,803 and 6,548,083;Shell et al., U.S. Pat. No. 6,635,280; and Conte et al., U.S. Pat. No.5,780,057).

In a swelling and expanding system, dosage forms that swell and changedensity in relation to the surrounding gastric content may be retainedin the stomach for longer than a conventional dosage form. A dosage formcan absorb water and swell to form a gelatinous outside surface andfloat on the surface of gastric content surface while maintainingintegrity before releasing a drug. Fatty materials may be added toimpede wetting and enhance flotation when hydration and swelling aloneare insufficient. Materials that release gases may also be incorporatedto reduce the density of a gastric retention dosage form. Swelling alsomay significantly increase the size of a dosage form and thereby impededischarge of the non-disintegrated swollen solid dosage form through thepylorus into the small intestine. Swellable dosage forms may be formedby encapsulating a core containing drug and a swelling agent, or bycombining a drug, swelling agent, and one or more erodible polymers.

Gastric retention dosage forms may also be in the form of a folded thinsheet containing a drug and water-insoluble diffusible polymer thatopens in the stomach to its original size and shape, which issufficiently large to prevent or inhibit passage of the expanded dosagefrom through the pyloric sphincter.

Floating and buoyancy gastric retention dosage forms may be designed totrap gases within sealed encapsulated cores that can float on thegastric contents, and thereby be retained in the stomach for a longertime, e.g., 9 to 12 hours. Due to the buoyancy effect, these systems canprovide a protective layer preventing the reflux of gastric content intothe esophageal region and can also be used for controlled releasedevices. A floating system may, for example, contain hollow corescontaining drug coated with a protective membrane. The trapped air inthe cores floats the dosage from on the gastric content until thesoluble ingredients are released and the system collapses. In otherfloating systems, cores contain drug and chemical substances capable ofgenerating gases when activated. For example, coated cores, containingcarbonate and/or bicarbonate can generate carbon dioxide in the reactionwith hydrochloric acid in the stomach or incorporated organic acid inthe system. The gas generated by the reaction is retained to float thedosage form. The inflated dosage form later collapses and clears fromthe stomach when the generated gas permeates slowly through theprotective coating.

Bioadhesive polymers can also provide a vehicle for controlled deliveryof drugs to a number of mucosal surfaces in addition to the gastricmucosa (see, e.g., Mathiowitz et al., U.S. Pat. No. 6,235,313; and Illumet al., U.S. Pat. No. 6,207,197). A bioadhesive system can be designedby incorporation of a drug and other excipients within a bioadhesivepolymer. On ingestion, the polymer hydrates and adheres to the mucusmembrane of the gastrointestinal tract. Bioadhesive polymers can beselected that adhere to a desired region or regions of thegastrointestinal tract. Bioadhesive polymers may be selected tooptimized delivery to targeted regions of the gastrointestinal tractincluding the stomach and small intestine. The mechanism of the adhesionis thought to be through the formation of electrostatic and hydrogenbonding at the polymer-mucus boundary. Jacob et al., U.S. ApplicationPublication Nos. 2006/0045865 and 2005/0064027 disclose bioadhesivedelivery systems which are useful for drug delivery to both the upperand lower gastrointestinal tract.

Ion exchange resins have also been shown to prolong gastric retention,potentially by adhesion.

Gastric retention oral dosage forms may be appropriately used fordelivery of drugs that are absorbed mainly from the uppergastrointestinal tract. For example, certain compounds of Formula (I)may exhibit limited colonic absorption, and be absorbed primarily fromthe upper gastrointestinal tract. Thus, dosage forms that release thecompound of Formula (I) in the upper gastrointestinal tract and/orretard transit of the dosage form through the upper gastrointestinaltract will tend to enhance the oral bioavailability of the compound ofFormula (I). Other forms comprising a compound of Formula (I) disclosedherein can be appropriately used with gastric retention dosage forms.

Polymer matrices have also been used to achieve controlled release ofthe drug over a prolonged period of time. Such sustained or controlledrelease can be achieved by limiting the rate by which the surroundinggastric fluid can diffuse through the matrix and reach the drug,dissolve the drug and diffuse out again with the dissolved drug, or byusing a matrix that slowly erodes, continuously exposing fresh drug tothe surrounding fluid. Examples of polymer matrices that function bythese methods are disclosed, for example, in Skinner, U.S. Pat. Nos.6,210,710 and 6,217,903; Rencher et al., U.S. Pat. No. 5,451,409; Kim,U.S. Pat. No. 5,945,125; Kim, PCT International Publication No. WO96/26718; Ayer et al., U.S. Pat. No. 4,915,952; Akhtar et al., U.S. Pat.No. 5,328,942; Fassihi et al., U.S. Pat. No. 5,783,212; Wong et al.,U.S. Pat. No. 6,120,803; and Pillay et al., U.S. Pat. No. 6,090,411.

Other drug delivery devices that remain in the stomach for extendedperiods of time include, for example, hydrogel reservoirs containingparticles (Edgren et al., U.S. Pat. No. 4,871,548); swellablehydroxypropylmethylcellulose polymers (Edgren et al., U.S. Pat. No.4,871,548); planar bioerodible polymers (Caldwell et al., U.S. Pat. No.4,767,627); plurality of compressible retention arms (Curatolo et al.,U.S. Pat. No. 5,443,843); hydrophilic water-swellable, cross-linkedpolymer particles (Shell, U.S. Pat. No. 5,007,790); andalbumin-cross-linked polyvinylpyrrolidone hydrogels (Park et al., J.Controlled Release 1992,19, 131-134).

In certain embodiments, pharmaceutical compositions of the presentdisclosure may be practiced with a number of different dosage forms,which may be adapted to provide sustained release of the compound ofFormula (I) upon oral administration. Sustained release oral dosageforms can be used to release drugs over a prolonged time period and areuseful when it is desired that a drug or drug form be delivered to thelower gastrointestinal tract. Sustained release oral dosage formsinclude diffusion-controlled systems such as reservoir devices andmatrix devices, dissolution-controlled systems, osmotic systems, anderosion-controlled systems. Sustained release oral dosage forms andmethods of preparing the same are well known in the art (see, e.g., “TheScience and Practice of Pharmacy,” Lippincott, Williams & Wilkins, 21stedition, 2005, Chapters 46 and 47; Langer, Science 1990,249, 1527-1533;and Rosoff, “Controlled Release of Drugs,” 1989, Chapter 2).

In diffusion-controlled systems, a water-insoluble polymer controls theflow of fluid and the subsequent egress of dissolved drug from thedosage form. Both diffusional and dissolution processes are involved inrelease of drug from the dosage form. In reservoir devices, a corecomprising a drug is coated with the polymer, and in matrix systems, thedrug is dispersed throughout the matrix. Cellulose polymers such asethylcellulose or cellulose acetate can be used in reservoir devices.Examples of materials useful in matrix systems include methacrylates,acrylates, polyethylene, acrylic acid copolymers, polyvinylchloride,high molecular weight polyvinylalcohols, cellulose derivates, and fattycompounds such as fatty acids, glycerides, and carnauba wax.

In dissolution-controlled systems, the rate of dissolution of the drugis controlled by slowly soluble polymers or by microencapsulation. Oncethe coating is dissolved, the drug becomes available for dissolution. Byvarying the thickness and/or the composition of the coating or coatings,the rate of drug release can be controlled. In somedissolution-controlled systems, a fraction of the total dose cancomprise an immediate-release component. Dissolution-controlled systemsinclude encapsulated/reservoir dissolution systems and matrixdissolution systems. Encapsulated dissolution systems can be prepared bycoating particles or granules of drug with slowly soluble polymers ofdifferent thickness or by microencapsulation. Examples of coatingmaterials useful in dissolution-controlled systems include gelatin,carnauba wax, shellac, cellulose acetate phthalate, and celluloseacetate butyrate. Matrix dissolution devices can be prepared, forexample, by compressing a drug with a slowly soluble polymer carrierinto a tablet form.

The rate of release of drug from osmotic pump systems is determined bythe inflow of fluid across a semipermeable membrane into a reservoir,which contains an osmotic agent. The drug is either mixed with the agentor is located in a reservoir. The dosage form contains one or more smallorifices from which dissolved drug is pumped at a rate determined by therate of entrance of water due to osmotic pressure. As osmotic pressurewithin the dosage form increases, the drug is released through theorifice(s). The rate of release is constant and can be controlled withintight limits yielding relatively constant plasma and/or bloodconcentrations of the drug. Osmotic pump systems can provide a constantrelease of drug independent of the environment of the gastrointestinaltract. The rate of drug release can be modified by altering the osmoticagent and the sizes of the one or more orifices.

The release of drug from erosion-controlled systems is determined by theerosion rate of a carrier matrix. Drug is dispersed throughout thepolymer and the rate of drug release depends on the erosion rate of thepolymer. The drug-containing polymer can degrade from the bulk and/orfrom the surface of the dosage form.

Sustained release oral dosage forms may be in any appropriate form fororal administration, such as, for example, in the form of tablets,pills, or granules. Granules can be filled into capsules, compressedinto tablets, or included in a liquid suspension. Sustained release oraldosage forms may additionally include an exterior coating to provide,for example, acid protection, ease of swallowing, flavor,identification, and the like.

In certain embodiments, sustained release oral dosage forms may comprisea therapeutically effective amount of a compound of Formula (I) and apharmaceutically acceptable vehicle. In certain embodiments, a sustainedrelease oral dosage form may comprise less than a therapeuticallyeffective amount of a compound of Formula (I), and a pharmaceuticallyeffective vehicle. Multiple sustained release oral dosage forms, eachdosage form comprising less than a therapeutically effective amount of acompound of Formula (I), may be administered at a single time or over aperiod of time to provide a therapeutically effective dose or regimenfor treating emesis in a patient.

Sustained release oral dosage forms of the present disclosure canrelease a compound of Formula (I) from the dosage form to facilitate theability of the compound of Formula (I) to be absorbed from anappropriate region of the gastrointestinal tract, for example, in thesmall intestine, or in the colon. In certain embodiments, a sustainedrelease oral dosage from may release a compound of Formula (I) from thedosage form over a period of at least about 4 hours, at least about 8hours, at least about 12 hours, at least about 16 hours, at least about20 hours, and in certain embodiments, at least about 24 hours. Incertain embodiments, a sustained release oral dosage form may release acompound of Formula (I) from the dosage form in a delivery pattern offrom about 0 wt % to about 20 wt % in about 0 to about 4 hours, about 20wt % to about 50 wt % in about 0 to about 8 hours, about 55 wt % toabout 85 wt % in about 0 to about 14 hours, and about 80 wt % to about100 wt % in about 0 to about 24 hours. In certain embodiments, asustained release oral dosage form may release a compound of Formula (I)from the dosage form in a delivery pattern of from about 0 wt % to about20 wt % in about 0 to about 4 hours, about 20 wt % to about 50 wt % inabout 0 to about 8 hours, about 55 wt % to about 85 wt % in about 0 toabout 14 hours, and about 80 wt % to about 100 wt % in about 0 to about20 hours. In certain embodiments, a sustained release oral dosage formmay release a compound of Formula (I) from the dosage form in a deliverypattern of from about 0 wt % to about 20 wt % in about 0 to about 2hours, about 20 wt % to about 50 wt % in about 0 to about 4 hours, about55 wt % to about 85 wt % in about 0 to about 7 hours, and about 80 wt %to about 100 wt % in about 0 to about 8 hours.

Sustained release oral dosage forms comprising a compound of Formula (I)may provide a concentration of levodopa in the plasma, blood, or tissueof a patient over time, following oral administration to the patient.The concentration profile of levodopa may exhibit an AUC that isproportional to the dose of the corresponding compound of Formula (I).

Regardless of the specific form of controlled release oral dosage formused, a compound of Formula (I) may be released from an orallyadministered dosage form over a sufficient period of time to provideprolonged therapeutic concentrations of the compound of Formula (I) inthe plasma and/or blood of a patient. Following oral administration, adosage form comprising a compound of Formula (I) may provide atherapeutically effective concentration of levodopa in the plasma and/orblood of a patient for a continuous time period of at least about 4hours, of at least about 8 hours, for at least about 12 hours, for atleast about 16 hours, and in certain embodiments, for at least about 20hours following oral administration of the dosage form to the patient.The continuous time periods during which a therapeutically effectiveconcentration of levodopa is maintained may be the same or different.The continuous period of time during which a therapeutically effectiveplasma concentration of levodopa is maintained may begin shortly afteroral administration or after a time interval.

In certain embodiments, an oral dosage for treating or preventing adisease, disorder, or condition in a patient can comprise a compound ofFormula (I), wherein the oral dosage form is adapted to provide, after asingle administration of the oral dosage form to the patient, atherapeutically effective concentration of levodopa in the plasma of thepatient for a first continuous time period selected from at least about4 hours, at least about 8 hours, at least about 12 hours, and at leastabout 16 hours, and at least about 20 hours.

An appropriate dose of the pharmaceutical composition may be determinedaccording to any one of several well-established protocols. For example,animal studies, such as studies using mice or rats, may be used todetermine an appropriate dose of a pharmaceutical compound. Results fromanimal studies may be extrapolated to determine doses for use in otherspecies, such as for example, humans. For example, the efficacy ofcompounds of Formula (I) and compositions thereof for treatingParkinson's disease may be assessed using animal models of Parkinson'sdisease and clinical studies.

Compounds of Formula (I) or pharmaceutical compositions thereof may beadministered as sustained release systems, and in certain embodiments,as orally administered sustained release systems. In certainembodiments, the compounds may be delivered by oral sustained releaseadministration. In certain embodiments, compounds of Formula (I) orpharmaceutical compositions thereof may be administered twice per day,in certain embodiments, once per day, and in certain embodiments atintervals greater than once per day.

Combination Therapy

In certain embodiments, at least one compound of Formula (I) thereof maybe used in combination therapy with at least one other therapeuticagent. Pharmaceutical compositions provided by the present disclosuremay include, in addition to at least one compound of Formula (I), one ormore therapeutic agents effective for treating the same or differentdisease, disorder, or condition.

Methods provided by the present disclosure include administration of atleast one compound of Formula (I) or pharmaceutical compositions thereofand one or more other therapeutic agents, provided that the combinedadministration does not inhibit the therapeutic efficacy of the at leastone compound of Formula (I) or levodopa and/or does not produce adversecombination effects.

Compounds of Formula (I) and another therapeutic agent or agents may actadditively or synergistically. In certain embodiments, pharmaceuticalcompositions provided by the present disclosure can be administeredconcurrently with the administration of another therapeutic agent, whichmay be contained in the same pharmaceutical composition as, or in adifferent composition from that containing at least one compound ofFormula (I). In certain embodiments, at least one compound of Formula(I) may be administered prior or subsequent to administration of anothertherapeutic agent. In certain embodiments of combination therapy, thecombination therapy can comprise alternating between administering acomposition provided by the present disclosure and a compositioncomprising another therapeutic agent, e.g., to minimize adverse sideeffects associated with a particular drug. When a compound of Formula(I) is administered concurrently with another therapeutic agent that canpotentially produce adverse side effects including, but not limited to,toxicity, the therapeutic agent may advantageously be administered at adose that falls below the threshold at which the adverse side effect iselicited.

In certain embodiments, at least one compound of Formula (I) may furtherbe administered together with one or more compounds that enhance,modulate, and/or control the release, bioavailability, therapeuticefficacy, therapeutic potency, and/or stability of the at least onecompound of Formula (I) or crystalline form thereof and/or levodopa. Forexample, to enhance therapeutic efficacy a compound of Formula (I) maybe co-administered with one or more active agents to increase theabsorption or diffusion of a compound of Formula (I) and/or levodopathrough the gastrointestinal tract, or to modify degradation of the (acompound of Formula (I) and/or levodopa in the systemic circulation. Incertain embodiments, a compound of Formula (I) may be co-administeredwith an active agent having pharmacological effects that enhance thetherapeutic efficacy of levodopa after being released from the compoundof Formula (I). In certain embodiments, a compound of Formula (I) may beco-administered with an active agent having pharmacological effects thatenhance the therapeutic efficacy of dopamine after being released fromlevodopa.

In certain embodiments, a compound of Formula (I) or pharmaceuticalcompositions comprising a compound of Formula (I) may be administered toa patient together with another compound for treating Parkinson'sdisease, depression, attention deficit disorder, schizophrenia, manicdepression, cognitive impairment disorders, restless legs syndrome,periodic limb movement disorders, tardive dyskinesia, Huntington'sdisease, Tourette's syndrome, hypertension, addictive disorders,congestive heart failure, stroke, excessive daytime sleepiness,dystonia, memory and learning deficits or loss, and Lewy Body disease.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatingParkinson's disease in combination with a therapy or another therapeuticagent known or believed to be effective in treating Parkinson's disease.Examples of drugs useful for treating Parkinson's disease includeamantadine, baclofen, biperiden, benztropine, orphenadrine,procyclidine, trihexyphenidyl, levodopa, carbidopa, andropinirole,apomorphine, benserazide, bromocriptine, budipine, cabergoline,eliprodil, eptastigmine, ergoline, galanthamine, lazabemide, lisuride,mazindol, memantine, mofegiline, pergolide, piribedil, pramipexole,propentofylline, rasagiline, remacemide, ropinirole, selegiline,spheramine, terguride, entacapone, and tolcapone.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatingdepression in combination with a therapy or another therapeutic agentknown or believed to be effective in treating depression. Examples ofdrugs useful for treating mood disorders such as depression includetricyclic antidepressants such as amitriptyline, amoxapine,clomipramine, desipramine, doxepin, imipramine, maprotiline,nortriptyline, protriptyline, and trimipramine; selective serotoninreuptake inhibitors such as citalopram, escitalopram, fluoxetine,fluvoxamine, paroxetine, and sertraline; serotonin-noradrenalinereuptake inhibitors such as venlafaxine, duloxetine, sibutramine, andmilnacipran; monoamine oxidase inhibitors such as phenelzine andtranylcypromine; and psychostimulants such as dextroamphetamine andmethylphenidate. Other antidepressants include benmoxine, butriptyline,dosulepin, imipramine, kitanserin, lofepramine, medifoxamine, mianserin,mirtazapine, viloxazine, cotinine, nisoxetine, reboxetine, tianeptine,acetaphenazine, binedaline, brofaromine, cericlamine, clovoxamine,iproniazid, isocarboxazid, moclobemide, phenyhydrazine, selegiline,sibutramine, ademetionine, adrafinil, amesergide, amisulpride,amperozide, benactyzine, bupropion, caroxazone, gepirone, idazoxan,metralindole, minaprine, nefazodone, nomifensine, ritanserin, roxindole,S-adenosylmethionine, escitalopram, tofenacin, trazodone, tryptophan,zalospirone, and Saint John's wort. A compound of Formula (I) orcrystalline form thereof and pharmaceutical compositions thereof mayalso be used in conjunction with psychotherapy or electroconvulsivetherapy to treat mood disorders such as depression.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatingattention deficit disorder in combination with a therapy or anothertherapeutic agent known or believed to be effective in treatingattention deficit disorder. Examples of drugs useful for treatingattention deficit disorder include atomoxetine, bupropion,dexmethylphenidate, dextroamphetamine, metamphetamine, methylphenidate,and pemoline.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatingschizophrenia in combination with a therapy or another therapeutic agentknown or believed to be effective in treating schizophrenia. Examples ofdrugs for treating schizophrenia include aripiprazole, loxapine,mesoridazine, quetiapine, reserpine, thioridazine, trifluoperazine, andziprasidone.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treating manicdepression in combination with a therapy or another therapeutic agentknown or believed to be effective in treating manic depression. Examplesof drugs useful for treating manic depression include carbamazepine,clonazepam, clonidine, valproic acid, verapamil, lamotrigine,gabapentin, topiramate, lithium, clozapine, olanzapine, risperidone,quetiapine, ziprasidone, clonazepam, lorazepam, zolipidem, St. John'swort, and omega-3 fatty acids.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatingcognitive and memory disorders in combination with a therapy or anothertherapeutic agent known or believed to be effective in treatingcognitive and memory disorders. Examples of drugs useful for treatingcognitive or memory disorders include antipsychotic drugs such aschlorpromazine, fluphenazine, haloperidol, loxapine, mesoridazine,molindone, perphenazine, pimozide, thioridazine, thiothixene,trifluoperazine, aripiprazole, clozapine, olanzapine, quetiapine,risperidone, and ziprasidone; sedatives such as diazepam and lorazepam;benzodiazepines such as alprazolam, chlordiazepoxide, clonazepam,clorazepate, diazepam, lorazepam, and oxazepam; nonsteroidalanti-inflammatory drugs such as aceclofenac, acetaminophen,alminoprofen, amfenac, aminopropylon, amixetrine, aspirin, benoxaprofen,bromfenac, bufexamac, carprofen, celecoxib, choline, salicylate,cinchophen, cinmetacin, clopriac, clometacin, diclofenac, diflunisal,etodolac, fenoprofen, flurbiprofen, ibuprofen, indomethacin, indoprofen,ketoprofen, ketorolac, mazipredone, meclofenamate, nabumetone, naproxen,parecoxib, piroxicam, pirprofen, rofecoxib, sulindac, tolfenamate,tolmetin, and valdecoxib; acetylcholinesterase inhibitors such asdonepezil, galantamine, rivastigmine, physostigmine, and tacrine; andN-methyl-D-aspartate (NMDA) receptor blockers such as memantine.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatingrestless legs syndrome in combination with a therapy or anothertherapeutic agent known or believed to be effective in treating restlesslegs syndrome. Examples of drugs useful for treating restless legssyndrome include dopaminergics such as levodopa, pergolide mesylate,pramipexole, and rinirole hydrochloride, benzodiazepines such asclonazepam and diazepam, opioids such as codeine, propoxyphene, andoxycodone, and anticonvulsants such as gabapentin, pregabalin, andcarbamazepine.

In certain embodiments, compounds of Formula (I) and pharmaceuticalcompositions thereof may be administered to a patient for treating amovement disorder in combination with a therapy or another therapeuticagent known or believed to be effective in treating a movement disorder.In certain embodiments, a movement disorder is tardive dyskinesia.Examples of drugs useful for treating movement disorders include mildsedatives such as benzodiazepines including alprazolam,chlordiazepoxide, clonazepam, clorazepate, diazepam, lorazepam, andoxazepam; muscle relaxants such as baclofen, anticholinergic drugs suchas trihexyphenidyl and diphenhydramine; antipsychotics such aschlorpromazine, fluphenazine, haloperidol, loxapine, mesoridazine,molindone, perphenazine, pimozide, thioridazine, thiothixene,trifluoperazine, aripiprazole, clozapine, olanzapine, quetiapine,risperidone, and ziprasidone; and antidepressants such as amitriptyline.Examples of drugs useful for treating tardive dyskinesia include vitaminE, dizocilpine, memantine, clzapine, lorazepam, diazepam, clonazepam,glycine, D-cycloserine valproic acid, amantadine, ifenprodil, reserpine,and tetrabenazine.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatingHuntington's disease in combination with a therapy or anothertherapeutic agent known or believed to be effective in treatingHuntington's disease. Examples of drugs useful for treating Huntington'sdisease include antipsychotics such as haloperidol, chlorpromazine, andolanzapine; antidepressants such as fluoxetine, sertralinehydrochloride, and nortriptyline; tranquilizers such as benzodiazepines,paroxetine, venlafaxin, and beta-blockers; mood-stabilizers such aslithium, valproate, and carbamazepine; and Botulinum toxin.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatingTourette's syndrome in combination with a therapy or another therapeuticagent known or believed to be effective in treating Tourette's syndrome.Examples of drugs useful for treating Tourette's syndrome includehaloperidol, pergolide, and pimozide.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatinghypertension in combination with a therapy or another therapeutic agentknown or believed to be effective in treating hypertension. Examples ofdrugs useful for treating hypertension include acebutolol, amiloride,amlodipine, atenolol, benazepril, betaxolol, bisoprolol, candesartancaptopril, careolol, carvedilol, chlorothiazide, chlorthalidone,clonidine, diltiazem, doxazosin, enalapril, eplerenone, eprosartan,felodipine, fosinopril, furosemide, guanabenz, guanethidine, guanfacine,hydralazine, hydrochlorothiazide, indapamide, irbesartan, isradipine,labetalol, lisinopril, losartan, methyldopa, metolazone, metoprolol,minoxidil, moexipril, nadolol, nicardipine, nifedipine, nisoldipine,nitroglycerin, olmesartan, perindopril, pindolol, prazosin, propranolol,quinapril, ramipril, reserpine, spironolactone, telmisartan, terazosin,timolol, torsemide, trandolapril, valsartan, and verapamil.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatingalcohol addiction and abuse in combination with a therapy or anothertherapeutic agent known or believed to be effective in treating alcoholaddiction and abuse. Examples of drugs useful for treating alcoholaddiction or abuse include disulfuram, naltrexone, clonidine, methadone,1-α-acetylmethadol, buprenorphine, and bupropion.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatingnarcotic addiction and abuse in combination with a therapy or anothertherapeutic agent known or believed to be effective in treating narcoticaddiction and abuse. Examples of drugs useful for treating narcoticaddiction or abuse include buprenorphine, tramadol, methadone, andnaltrexone.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatingnicotine addiction and abuse in combination with a therapy or anothertherapeutic agent known or believed to be effective in treating nicotineaddiction and abuse. Examples of drugs useful for treating nicotineaddiction or abuse include bupropion, clonidine, and nicotine.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatingcongestive heart failure in combination with a therapy or anothertherapeutic agent known or believed to be effective in treatingcongestive heart failure. Examples of drugs useful for treatingcongestive heart failure include alllopurinol, amiloride, amlodipine,benazepril, bisoprolol, carvedilol, digoxin, enalapril, eplerenone,fosinopril, furosemide, hydrochlorothiazide, hydralazine, isosorbidedinitrate, isosorbide mononitrate, lisinopril, metoprolol, moexipril,nesiritide, nicardipine, nifedipine, nitroglycerin, perindopril,prazosin, quinapril, ramipril, spironolactone, torsemide, trandolapril,triamcinolone, and valsartan.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatingexcessive daytime sleepiness in combination with a therapy or anothertherapeutic agent known or believed to be effective in treatingexcessive daytime sleepiness. Examples of drugs useful for treatingexcessive daytime sleepiness include dextroamphetamine, methylphenidate,modafinil, sodium oxylate, clonidine, bromocriptine, antidepressants,and monoamine oxidase inhibitors.

In certain embodiments, a compound of Formula (I) or a pharmaceuticalcomposition thereof may be administered to a patient for treatingdystonia in combination with a therapy or another therapeutic agentknown or believed to be effective in treating dystonia. Examples ofdrugs useful for treating dystonia include Botulinum-toxin, clonazepam,lorazepam, trihexyphenidyl, baclofen, diazepam, tetrabenazine,cyclobenzaprine, carbamazepine, and benzatropine.

EXAMPLES

The invention is further defined by reference to the following examples,which describe synthesis, properties, and uses of catechol protectedlevodopa diester prodrugs of Formula (I). It will be apparent to thoseskilled in the art that many modifications, both to materials andmethods, may be practiced without departing from the scope of thedisclosure.

Example 1 (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-3-(3,4-Dihydroxyphenyl)-2-[(tert-butoxy)carbonylamino]propanoate(Intermediate) (1) Step 1:(2R)-1-(tert-Butyldimethyl-1-silyloxy)propan-2-ol (2)

(R)-(−)-1,2-propanediol (5 g, 65.7 mmol) and imidazole (4.47 g, 65.7mmol) were dissolved in anhydrous dichloromethane. A solution ofchlorodimethyl-butylsilane (9.9 g, 65.7 mmol) in dichloromethane wasadded at 0° C. The mixture was stirred at 0° C. for 2 hours. Afterfiltration the filtrate was dried over Na₂SO₄. Concentration gave 12.5 g(100% yield) of title compound (2), which was used in next reactionwithout further purification. ¹H NMR (400 MHz, CDCl₃): δ 0 (6H, s), 0.83(9H, s), 1.04 (3H, d, J=6.4 Hz), 2.64 (1H, s, br), 3.26 (1H, dd, J=8,9.6 Hz), 3.50 (1H, dd, J=9.6, 3.2 Hz), 3.74 (1H, m).

Step 2: (1R)-1-Methyl-2-(tert-butyldimethylsilyloxy)ethyl(2S)-2-[(tert-Butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(3)

N-Boc-L-DOPA(OBn)₂COOH (3.6 g, 7.5 mmol) was dissolved in anhydrousdichloromethane. To the solution added triethylamine (2.6 mL, 18.5mmol), 2,4,6-trichlorobenzoyl chloride (1.4 mL, 9 mmol), and stirred for30 min. A solution of (2R)-1-(tert-butyldimethyl-1-silyloxy)propan-2-ol(2) (1.7 g, 9 mmol) in dichloromethane was slowly added to the reactionmixture, followed by catalytic amount of 4-(dimethylamino)pyridine. Themixture was stirred at room temperature for 16 hours, then washed with10% citric acid, dried over Na₂SO₄, and concentrated. Chromatography(silica gel, 10% ethyl acetate in hexane) afforded 3.4 g (70% yield) ofthe title compound (3). ¹H NMR (400 MHz, CDCl₃): δ 0.08 (6H, s), 0.88(9H, s), 1.12 (3H, d, J=6.4 Hz), 1.42 (9H, s), 2.99 (2H, m), 3.35 (1H,m), 3.59 (1H, m), 3.84 (1H, m), 4.50 (1H, m), 4.89 (1H, d, NH), 5.10(4H, s), 6.60 (1H, d, J=8 Hz), 6.71 (1H, s), 6.87 (1H, d, J=8 Hz),7.26-7.43 (10H, m).

Step 3: (1R)-2-Hydroxy-isopropyl(2S)-2-[(tert-Butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(4)

(1R)-1-Methyl-2-(tert-butyldimethylsilyloxy)ethyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(3) (3.4 g, 5.2 mmol) was dissolved in anhydrous tetrahydrofuran.Triethylamine trihydrofluoride was slowly added. The mixture was stirredat room temperature for 4 hours, and the solvent was evaporated underreduced pressure. Chromatography (silica gel, 30% ethyl acetate inhexane) gave 2.5 g (90% yield) of the title compound (4). ¹H NMR (400MHz, CDCl₃): δ 1.09 (3H, d, J=6.4 Hz), 1.41 (9H, s), 2.78 (1H, s, br),2.96 (2H, m), 3.51 (1H, m), 3.59 (1H, m), 4.34 (1H, m), 4.98 (1H, m),5.05 (1H, d, NH), 5.10 (4H, s), 6.66 (1H, d, J=8 Hz), 6.77 (1H, s), 6.83(1H, d, J=8 Hz), 7.26-7.43 (10H, m).

Step 4: (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-[(tert-Butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(5)

Benzoic acid (0.57 g, 4.67 mmol) and (1R)-2-hydroxy-isopropyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(4) (2.5 g, 4.67 mmol) was dissolved in 60 mL of anhydrousdichloromethane. A solution of 1,3-dicyclohexylcarbodiimide (1.15 g, 5.6mmol) in dichloromethane was slowly added, followed by a catalyticamount of 4-(dimethylamino)pyridine. The mixture was stirred at roomtemperature for 16 hours. After filtration, the filtrate was washed with5% NaHCO₃ and dried over Na₂SO₄. Chromatography (silica gel, 10% ethylacetate in hexane) gave 2.6 g (87% yield) of the title compound (5). ¹HNMR (400 MHz, CDCl₃): δ 1.23 (3H, d, J=6.4 Hz), 1.41 (9H, s), 2.98 (2H,m), 4.26 (1H, m), 4.33 (1H, m), 4.51 (1H, m), 4.93 (1H, d, NH), 5.10(4H, s), 5.24 (1H, m), 6.65 (1H, d, J=8 Hz), 6.76 (1H, s), 6.81 (1H, d,J=8 Hz), 7.25-7.45 (12H, m), 7.54 (1H, t, J=7.6 Hz), 8.00 (2H, d, J=7.6Hz).

Step 5: (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-3-(3,4-Dihydroxyphenyl)-2-[(tert-butoxy)carbonylamino]propanoate(1)

To a solution of (1R)-1-methyl-2-phenylcarbonyloxyethyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(5) (2.6 g, 4.85 mmol) in 40 mL of tetrahydrafuran, 10% Pd—C (200 mg)pre-mixed with 10 mL of methanol was added under a nitrogen atmosphere.The nitrogen atmosphere was exchanged with hydrogen using the evacuationrefill cycle method. The mixture was stirred under hydrogen at roomtemperature for 2 hours. After filtration and washing with methanol, thefiltrate was concentrated and chromatographed (silica gel, 30% ethylacetate in hexane) to afford 1.87 g (100% yield) of the title compound(1). MS (ESI) m/z 460.20 (M+H)⁺ and 458.17 (M−H)⁻.

Example 2 (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (6) Step 1: (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-3-[3,4-bis(ethoxycarbonyloxy)phenyl]-2-[(tert-butoxy)carbonylamino]propanoate(7)

To a mixture of (1R)-1-methyl-2-phenylcarbonyloxyethyl(2S)-3-(3,4-dihydroxyphenyl)-2-[(tert-butoxy)carbonylamino]propanoate(1) (1.73 g, 3.76 mmol) and ethyl chloroformate (0.861 mL, 9.02 mmol) inanhydrous dichloromethane, triethylamine (1.26 mL, 9.02 mmol) was addedat 0° C. The reaction mixture was stirred at 0° C. for 1 hour. Theresulting solution was partitioned between dichloromethane and 10%citric acid, washed with water, dried over MgSO₄, and concentrated todryness. Purification by silica gel chromatography (20% ethyl acetate inhexane) provided the title compound (7) (1.6 g, 70% yield) as a whitesolid. MS (ESI) m/z 626.20 (M+Na)⁺.

Step 2: (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (6)

(1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-3-[3,4-bis(ethoxycarbonyloxy)phenyl]-2-[(tert-butoxy)carbonylamino]propanoate(7) (1.6 g, 2.65 mmol) was dissolved in 10 mL of 4M HCl in dioxane. Thereaction mixture was stirred at room temperature for 60 min. Dioxane wascompletely evaporated under reduced pressure. The resulting white solidwas dissolved in water (15 mL) and washed with methyl tert-butyl ether.The aqueous phase was collected and mixed with acetonitrile (10 mL).Lyophilization gave the title compound (6) (1.4 g, 100% yield) as awhite solid. ¹H NMR (400 MHz, CD₃OD): δ 1.31 (3H, d, J=6.8 Hz), 1.35(6H, t, J=6.8 Hz), 3.23 (1H, d, J=3.2 Hz), 3.25 (1H, d, J=4 Hz), 4.28(4H, q, 6.8 Hz), 4.31 (1H, dd, J=14, 5.6 Hz), 4.38 (1H, t, J=7.2 Hz),4.49 (1H, dd, J=12, 3.2 Hz), 5.35 (1H, m), 7.24 (1H, d, J=2 Hz), 7.27(1H, d, J=8 Hz), 7.28 (1H, d, J=2 Hz), 7.48 (2H, t, J=7.2 Hz), 7.61 (1H,t, J=7.2 Hz), 8.02 (2H, d, J=7.6 Hz). MS (ESI) m/z 504.16 (M+H)⁺.

Example 3 (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-Amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoateHydrochloride (8) Step 1: (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-3-[3,4-Bis(isopropoxycarbonyloxy)phenyl]-2-[(tert-butoxy)carbonylamino]propanoate(9)

To a mixture of (1R)-1-methyl-2-phenylcarbonyloxyethyl(2S)-3-(3,4-dihydroxyphenyl)-2-[(tert-butoxy)carbonylamino]propanoate(1) (1.1 g, 2.4 mmol) and isopropyl chloroformate (1M in toluene, 5.76mL, 5.76 mmol) in anhydrous dichloromethane, triethylamine (0.8 mL, 5.76mmol) was added at 0° C. The reaction mixture was stirred at 0° C. for 1hour. The resulting solution was partitioned between dichloromethane and10% citric acid, washed with water, dried over MgSO₄, and concentratedto dryness. Purification by silica gel chromatography (20% ethyl acetatein hexane) provided the title compound (9) (1.06 g, 70% yield) as awhite solid. MS (ESI) m/z 654.09 (M+Na)⁺.

Step 2: (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-Amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoateHydrochloride (8)

(1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]-2-[(tert-butoxy)carbonylamino]propanoate(9) (1.06 g, 1.63 mmol) was dissolved in 10 mL of 4M HCl in dioxane. Thereaction mixture was stirred at room temperature for 60 min. Dioxane wasevaporated completely under reduced pressure. The resulting white solidwas dissolved in water (15 mL) and washed with methyl tert-butyl ether.The aqueous phase was collected and mixed with acetonitrile (10 mL).Lyophilization gave the title compound (8) (0.926 g, 100% yield) as awhite solid. ¹H NMR (400 MHz, CD₃OD): δ 1.30 (3H, d, J=6.4 Hz), 1.35(12H, d, J=6.4 Hz), 3.16 (1H, dd, J=14.4, 6.8 Hz), 3.23 (1H, dd, J=14.4,6.4 Hz), 4.28 (1H, t, J=6.8 Hz), 4.31 (1H, dd, J=12.4, 6.4 Hz), 4.48(1H, dd, J=12, 2.8 Hz), 5.33 (1H, m), 7.19 (1H, dd, J=8.2 Hz), 7.24 (1H,d, J=2 Hz), 7.25 (1H, d, J=8 Hz), 7.48 (2H, t, J=7.2 Hz), 7.60 (1H, t,J=7.2 Hz), 8.00 (2H, d, J=7.6 Hz). MS (ESI) m/z 532.21 (M+H)⁺.

Example 4 (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-Amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoateHydrochloride (10) Step 1: (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-[(tert-Butoxy)carbonylamino]-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate(11)

To a mixture of (1R)-1-methyl-2-phenylcarbonyloxyethyl(2S)-3-(3,4-dihydroxyphenyl)-2-[(tert-butoxy)carbonylamino]propanoate(1) (1.38 g, 3 mmol) and isobutyryl chloride (0.768 mL, 7.2 mmol) inanhydrous dichloromethane, triethylamine (1.0 mL, 7.2 mmol) was added at0° C. The reaction mixture was stirred at 0° C. for 1 hour. Theresulting solution was partitioned between dichloromethane and 10%citric acid, washed with water, dried over MgSO₄, and concentrated todryness. Purification by silica gel chromatography (20% ethyl acetate inhexane) provided the title compound (11) (1.25 g, 66% yield) as a whitesolid. MS (ESI) m/z 622.19 (M+Na)⁺.

Step 2: (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-Amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoateHydrochloride (10)

(1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate(1.25 g, 2.0 mmol) was dissolved in 20 mL of 2M HCl in dioxane. Thereaction mixture was stirred at room temperature for 60 min. Dioxane wascompletely evaporated under reduced pressure. The resulting white solidwas dissolved in water (15 mL) and washed with methyl tert-butyl ether.The aqueous phase was collected and mixed with acetonitrile (10 mL).Lyophilization gave the title compound (10) (0.66 g, 62% yield) as awhite solid. ¹H NMR (400 MHz, CD₃OD): δ 1.27 (6H, d, J=7.2 Hz), 1.28(6H, d, J=7.2 Hz), 1.30 (3H, d, J=6.4 Hz), 2.8 (2H, m), 3.17 (1H, dd,J=14.4, 6.8 Hz), 3.20 (1H, dd, J=14.4, 6.4 Hz), 4.25 (1H, t, J=6.8 Hz),4.31 (1H, dd, J=12.4, 6.4 Hz), 4.47 (1H, dd, J=12, 3.2 Hz), 5.31 (1H,m), 7.12(1H, d, J=8 Hz), 7.14 (1H, d, J=2 Hz), 7.18 (1H, dd, J=8.2 Hz),7.47 (2H, t, J=7.2 Hz), 7.58 (1H, t, J=7.2 Hz), 8.02 (2H, d, J=7.6 Hz).MS (ESI) m/z 500.16 (M+H)⁺.

Example 5 (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-[(tert-Butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoateHydrochloride (12) Step 1: (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-[(tert-Butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate(13)

To a mixture of (1R)-1-methyl-2-phenylcarbonyloxyethyl(2S)-3-(3,4-dihydroxyphenyl)-2-[(tert-butoxy)carbonylamino]propanoate(1) (1.1 g, 2.4 mmol) and trimethylacetyl chloride (0.708 mL, 5.76 mmol)in anhydrous dichloromethane, triethylamine (0.8 mL, 5.76 mmol) wasadded at 0° C. The reaction mixture was stirred at 0° C. for 1 hour. Theresulting solution was partitioned between dichloromethane and 10%citric acid, washed with water, dried over MgSO₄, and concentrated todryness. Purification by silica gel chromatography (20% ethyl acetate inhexane) provided the title compound (13) (1.03 g, 68% yield) as a whitesolid. MS (ESI) m/z 650.23 (M+Na)⁺.

Step 2: (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-[(tert-Butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoateHydrochloride (12)

(1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate(13) (1.03 g, 1.64 mmol) was dissolved in 20 mL of 4M HCl in dioxane.The reaction mixture was stirred at room temperature for 60 min. Dioxanewas completely evaporated under reduced pressure. The resulting whitesolid was dissolved in water (15 mL) and washed with methyl tert-butylether. The aqueous phase was collected and mixed with acetonitrile (10mL). Lyophilization gave the title compound (12) (0.851 g, 98% yield) asa white solid. ¹H NMR (400 MHz, CD₃OD): δ 1.30 (3H, d, J=6.4 Hz), 1.33(9H, s), 1.34 (9H, s), 3.13 (1H, dd, J=14.4, 6.8 Hz), 3.20 (1H, dd,J=14.4, 6.4 Hz), 4.22 (1H, t, J=6.8 Hz), 4.32 (1H, dd, J=12.4, 6.4 Hz),4.49 (1H, dd, J=12, 3.2 Hz), 5.33 (1H, m), 7.10 (1H, d, J=8 Hz), 7.11(1H, d, J=2 Hz), 7.17 (1H, dd, J=2, 8 Hz), 7.47 (2H, t, J=7.2 Hz), 7.58(1H, t, J=7.2 Hz), 8.02 (2H, d, J=7.6 Hz). MS (ESI) m/z 528.14 (M+H)⁺.

Example 6 (1R)-2-Acetyloxy-1-methylethyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (14) Step 1:(2R)-1-(tert-Butyldimethyl-1-silyloxy)propan-2-ol (15)

(R)-(−)-1,2-Propanediol (5.0 g, 65.7 mmol) and imidazole (4.5 g, 65.7mmol) were dissolved in anhydrous dichloromethane. A solution ofchlorodimethyl tert-butylsilane (9.9 g, 65.7 mmol) in dichloromethanewas added at 0° C. The mixture was stirred at 0° C. for 2 hours. Afterfiltration the filtrate was dried over Na₂SO₄. Concentration gave 12.5 g(100% yield) of title compound (15), which was used in the next reactionwithout further purification. ¹H NMR (400 MHz, CDCl₃): δ 0.08 (s, 6H),0.83 (s, 9H), 1.04 (d, J=6.4 Hz, 3H), 2.64 (s, br, 1H), 3.26 (dd, J=9.6,8.0 Hz, 1H), 3.50 (dd, J=9.6, 3.2 Hz, 1H), 3.74 (m, 1H).

Step 2: (1R)-1-Methyl-2-(tert-butyldimethylsilyloxy)ethyl(2S)-2-[(tert-Butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(16)

N-Boc-L-DOPA(OBn)₂COOH (38.2 g, 80.0 mmol),(2R)-1-(tert-butyldimethyl-1-silyloxy)propan-2-ol (15) (18.2 g, 96.0mmol) and dicyclohexylcarbodiimide (214.0 g, 100.0 mmol) were dissolvedin anhydrous dichloromethane. A catalytic amount of4-(dimethylamino)pyridine (0.6 g, 5.0 mmol) was added to the solution.The mixture was stirred at room temperature for 16 hours. Afterfiltration, the filtrate was washed with 10% citric acid, 5% sodiumbicarbonate, and brine. The organic layer was collected, dried overNa₂SO₄, and concentrated. Chromatography (silica gel, 15% ethyl acetatein hexane) gave 37.6 g (72% yield) of the title compound (16). ¹H NMR(400 MHz, CDCl₃): δ 0.08 (s, 6H), 0.88 (s, 9H), 1.12 (d, J=6.4 Hz, 3H),1.42 (s, 9H), 2.99 (m, 2H), 3.35 (m, 1H), 3.59 (m, 1H), 4.40 (m, 1H),4.82 (m, 1H), 4.85 (d, 1H, NH), 5.10 (s, 4H), 6.60 (d, J=8.0 Hz, 1H),6.71 (s, 1H), 6.87 (d, J=8.0 Hz, 1H), 7.26-7.43 (m, 10H).

Step 3: (1R)-2-Hydroxy-1-methylethyl(2S)-2-[(tert-Butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(17)

(1R)-1-Methyl-2-(tert-butyldimethylsilyloxy)ethyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(16) (4.7 g, 7.2 mmol) was dissolved in anhydrous tetrahydrofuran.Triethylamine trihydrofluoride (9.4 mL, 57.0 mmol) was slowly added. Themixture was stirred at room temperature for 4 hours. Removal of solventunder reduced pressure gave 3.8 g (98% yield) of the title compound. ¹HNMR (400 MHz, CDCl₃): δ 1.09 (d, J=6.4 Hz, 3H), 1.41 (s, 9H), 2.78 (s,1H, br), 2.96 (m, 2H), 3.51 (m, 1H), 3.68 (m, 1H), 4.36 (dd, J=14.0, 6.4Hz, 1H), 4.98 (m, 1H), 5.05 (d, 1H, NH), 5.10 (s, 4H), 6.66 (d, J=8.0Hz, 1H), 6.77 (s, 1H), 6.83 (d, J=8.0 Hz, 1H), 7.26-7.43 (m, 10H).

Step 4: (1R)-2-Acetyloxy-1-methylethyl(2S)-2-[(tert-Butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(18)

Acetyl chloride (2.3 mL, 33.1 mmol) and (1R)-2-hydroxy-1-methylethyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(17) (11.8 g, 22.1 mmol) were dissolved in 400 mL of anhydrousdichloromethane. A solution of pyridine (2.7 mL, 33.1 mmol) indichloromethane was added dropwise at 0° C. The mixture was stirred atroom temperature for 2 hours. The product was extracted withdichloromethane, washed with 5% NaHCO₃, 10% citric acid, and dried overNa₂SO₄. After concentration the resulting residue was further driedunder vacuum. The crude product (18) (12.9 g, 100% yield) was isolatedas a foamy solid. ¹H NMR (400 MHz, CDCl₃): δ 1.15 (d, J=6.4 Hz, 3H),1.43 (s, 9H), 2.03 (s, 3H), 2.95 (dd, J=14.0, 6.8 Hz, 1H), 3.01 (dd,J=14.0, 6.8 Hz, 1H), 3.99 (dd, J=12.0, 6.4 Hz, 1H), 4.12 (dd, J=12.0,3.2 Hz, 1H), 4.50 (dd, J=14.0, 6.8 Hz, 1H), 4.93 (d, 1H, NH), 5.07 (m,1H), 5.10 (s, 4H), 6.65 (dd, J=8.0, 2 Hz, 1H), 6.76 (d, J=2.0 Hz, 1H),6.84 (d, J=8.0 Hz, 1H), 7.28-7.46 (m, 10H).

Step 5: (1R)-2-Acetyloxy-1-methylethyl(2S)-3-(3,4-Dihydroxyphenyl)-2-[(tert-butoxy)carbonylamino]propanoate(19)

To a solution of (1R)-2-acetyloxy-1-methylethyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(18) (12.7 g, 22.1 mmol) in 100 mL of methanol, 10% Pd—C (200 mg)pre-mixed with 10 mL of methanol was added under a nitrogen atmosphere.The nitrogen was exchanged with hydrogen using the evacuation refillcycle method. The mixture was stirred under hydrogen at room temperaturefor 4 hours. After filtration and washing with methanol, the filtratewas concentrated to afford 8.8 g (100% yield) of the title compound(19). ¹H NMR (400 MHz, CDCl₃): δ 1.21 (d, J=6.4 Hz, 3H), 1.43 (s, 9H),2.07 (s, 3H), 2.95 (m, 2H), 4.05 (dd, J=12.0, 6.4 Hz, 1H), 4.12 (dd,J=12.0, 3.2 Hz, 1H), 4.48 (dd, J=14, 6.4 Hz, 1H), 5.04 (d, 1H, NH), 5.15(m, 1H), 6.53 (d, J=8.0 Hz, 1H), 6.66 (s, 1H), 6.74 (d, J=8.0 Hz, 1H).MS (ESI) m/z 420.0 (M+Na)⁺ and 396.0 (M−H)⁻.

Step 6: (1R)-2-Acetyloxy-1-methylethyl(2S)-3-[3,4-Bis(ethoxycarbonyloxy)phenyl]-2-[(tert-butoxy)carbonylamino]propanoate(20)

To a mixture of (1R)-2-acetyloxy-1-methylethyl(2S)-3-(3,4-dihydroxyphenyl)-2-[(tert-butoxy)carbonylamino]propanoate(19) (8.9 g, 22.4 mmol) and ethyl chloroformate (5.30 mL, 55.3 mmol) inanhydrous dichloromethane, triethylamine (7.7 mL, 55.3 mmol) was addedat 0° C. The reaction mixture was stirred at 0° C. for 1 hour. Thesolution was partitioned between dichloromethane and 10% citric acid andwashed with water. The organic layer was dried over MgSO₄, andconcentrated to dryness. Chromatography (30% ethyl acetate in hexane)provided the title compound (20) (11.5 g, 95% yield) as a white, foamysolid. ¹H NMR (400 MHz, CDCl₃): δ 1.17 (d, J=6.8 Hz, 3H), 1.37 (t, J=7.2Hz, 3H), 1.37 (t, J=7.2 Hz, 3H), 1.43 (s, 9H), 2.05 (s, 3H), 3.04 (m,2H), 4.00 (dd, J=12.0, 6.8 Hz, 1H), 4.14 (dd, J=12.0, 3.2 Hz, 1H), 4.32(q, J=7.2 Hz, 4H), 4.54 (dd, J=12.8, 6.4 Hz, 1H), 5.02 (d, J=8.0 Hz, 1H,NH), 5.12 (m, 1H), 7.05 (dd, J=8.0, 2.0 Hz, 1H), 7.08 (d, J=2.0 Hz, 1H),7.19 (d, J=8.0 Hz, 1H). MS (ESI) m/z 564.1 (M+Na)⁺ and 540.1 (M−H)⁻.

Step 7: (1R)-2-Acetyloxy-1-methylethyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (14)

(1R)-2-Acetyloxy-1-methylethyl(2S)-3-[3,4-bis(ethoxycarbonyloxy)phenyl]-2-[(tert-butoxy)carbonylamino]propanoate(20) (11.5 g, 21.2 mmol) was dissolved in 60 mL of 4M HCl in dioxane.The resulting mixture was stirred at room temperature for 60 min.Solvent removal under reduced pressure gave 10.1 g (100% yield) of thetitle compound (14) as a colorless oil. ¹H NMR (400 MHz, CD₃OD): δ 1.21(d, J=6.4 Hz, 3H), 1.35 (t, J=7.2 Hz, 3H), 1.36 (t, J=7.2 Hz, 3H), 2.04(s, 3H), 3.26 (d, J=7.2 Hz, 2H), 4.05 (dd, J=8.8, 6.4 Hz, 1H), 4.23 (dd,J=12.4, 3.2 Hz, 1H), 4.28 (q, J=6.8 Hz, 2H), 4.30 (q, J=6.8 Hz, 2H),4.37 (t, J=7.2 Hz, 1H), 5.19 (m, 1H), 7.27 (dd, J=8.0, 2.0 Hz, 1H), 7.30(d, J=2.0 Hz, 1H), 7.32 (d, J=8.0 Hz, 1H). MS (ESI) m/z 442.1 (M+H)⁺.

Example 7 (1R)-2-Acetyloxy-1-methylethyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate HydrogenFumarate (21)

(1R)-2-Acetyloxy-1-methylethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride (14) (10.5 g, 21.7 mmol) was mixed with ethyl acetate (250mL), and then quickly washed with 5% sodium bicarbonate (100 mL) at 0°C. The organic layer was separated, dried over MgSO₄, and thentransferred to a flask charged with a mixture of fumaric acid (2.5 g,21.8 mmol) and ethyl acetate. The mixture was stirred at roomtemperature for 30 min. The title compound (21) (9.1 g, 83% yield) wascrystallized and collected by filtration. M.p.: 78.1-80.7° C.(uncorrected). The melting point as determined using differentialscanning calorimeter (DSC) was 82.05° C. (melting enthalpy was 102 μg).¹H NMR (400 MHz, CD₃OD): δ 1.20 (d, J=6.4 Hz, 3H), 1.35 (t, J=6.8 Hz,3H), 1.36 (t, J=6.8 Hz, 3H), 2.03 (s, 3H), 3.17 (dd, J=14.0, 6.8 Hz,1H), 3.22 (dd, J=14.0, 6.8 Hz, 1H), 4.03 (dd, J=12.0, 6.4 Hz, 1H), 4.22(dd, J=12.0, 3.2 Hz, 1H), 4.23 (t, J=6.8 Hz, 1H), 4.29 (q, J=7.2 Hz,2H), 4.30 (q, J=7.2 Hz, 2H), 5.17 (m, 1H), 6.69 (s, 2H), 7.23 (dd,J=8.0, 2.0 Hz, 1H), 7.27 (d, J=2.0 Hz, 1H), 7.30 (d, J=8.0 Hz, 1H). MS(ESI) m/z 442.2 (M+H)⁺. Calc. For C₂₀H₂₇NO₁₀.2H₂O: C, 48.57; H, 5.94; N,2.36. Found: C, 48.64; H, 5.51; N, 2.38.

Example 8 (1R)-1-Methyl-2-(2-methylpropanoyloxy)ethyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (22)

Following the procedure of Example 6 and substituting acetyl chloridewith iso-butyryl chloride in Step 4 provided the title compound (22)(52% yield over 7 steps) as a colorless oil. ¹H NMR (400 MHz, CD₃OD): δ1.15 (d, J=6.4 Hz, 3H), 1.16 (d, J=6.4 Hz, 3H), 1.22 (d, J=6.4 Hz, 3H),1.35 (t, J=6.8 Hz, 3H), 1.36 (t, J=6.8 Hz, 3H), 2.57 (m, 1H), 3.24 (dd,J=14.0, 7.2 Hz, 1H), 3.27 (dd, J=14.0, 7.2 Hz, 1H), 4.06 (dd, J=12.0,5.6 Hz, 1H), 4.25 (dd, J=12.0, 3.2 Hz, 1H), 4.28 (q, J=6.8 Hz, 2H), 4.30(q, J=6.8 Hz, 2H), 4.35 (t, J=7.2 Hz, 1H), 5.19 (m, 1H), 7.25 (dd,J=8.0, 2.0 Hz, 1H), 7.29 (d, J=2.0 Hz, 1H), 7.32 (d, J=8.0 Hz, 1H). MS(ESI) m/z 492.0 (M+Na)⁺.

Example 9 (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (23)

Following the procedure of Example 6 and substituting acetyl chloridewith benzoyl chloride in Step 4 provided the title compound (23) (38%yield over 7 steps) as a white solid. ¹H NMR (400 MHz, CD₃OD): δ 1.31(d, J=6.8 Hz, 3H), 1.35 (t, J=6.8 Hz, 6H), 3.23 (dd, J=14.0, 3.2 Hz,1H), 3.25 (dd, J=14.0, 4.8 Hz, 1H), 4.28 (q, J=6.8 Hz, 4H), 4.31 (dd,J=14.0, 5.6 Hz, 1H), 4.38 (t, J=7.2 Hz, 1H), 4.49 (dd, J=12.0, 3.2 Hz,1H), 5.35 (m, 1H), 7.24 (dd, J=8.0, 2.0 Hz, 1H), 7.27 (d, J=2.0 Hz, 1H),7.28 (d, J=8.0 Hz, 1H), 7.48 (t, J=7.2 Hz, 2H), 7.61 (t, J=7.2 Hz, 1H),8.02 (d, J=7.6 Hz, 2H). MS (ESI) m/z 504.2 (M+H)⁺.

Example 10 (1R)-2-Ethoxycarbonyloxy-1-methylethyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (24)

Following the procedure describe of Example 6 and substituting acetylchloride with ethyl chloroformate in Step 4 provided the title compound(24) (30% yield over 7 steps) as a white solid. ¹H NMR (400 MHz, CDCl₃):δ 1.18 (d, J=6.4 Hz, 3H), 1.29 (t, J=7.2 Hz, 3H), 1.35 (t, J=6.8 Hz,3H), 1.36 (t, J=7.2 Hz, 3H), 3.36 (dd, J=14.4, 7.6 Hz, 1H), 3.52 (dd,J=14.4, 5.6 Hz, 1H), 4.07-4.19 (m, 4H), 4.26 (q, J=7.2 Hz, 2H), 4.27 (q,J=7.2 Hz, 2H), 4.39 (br. m, 1H), 5.13 (br. m, 1H), 7.22-7.32 (m, 3H),8.80 (br. s, 3H).

Example 11 (1R)-2-Acetyloxy-1-methylethyl(2S)-2-Amino-3-[3,4-bis(methylethoxycarbonyloxy)phenyl]propanoateHydrochloride (25)

Following the procedure of Example 6 and substituting ethylchloroformate with isopropyl chloroformate in Step 6 provided the titlecompound (25) (34% yield over 7 steps) as a colorless oil. ¹H NMR (400MHz, CD₃OD): δ 1.18 (d, J=6.4 Hz, 3H), 1.35 (d, J=6.0 Hz, 6H), 1.36 (d,J=6.0 Hz, 6H), 2.03 (s, 3H), 3.15 (d, J=6.8 Hz, 2H), 4.03 (dd, J=8.0,6.4 Hz, 1H), 4.12 (t, J=6.8 Hz, 1H), 4.21 (dd, J=12.0, 3.2 Hz, 1H), 4.92(m, 2H), 5.14 (m, 1H), 7.21 (dd, J=8.0, 2.0 Hz, 1H), 7.23 (d, J=2.0 Hz,1H), 7.27 (d, J=8.0 Hz, 1H). MS (ESI) m/z 470.1 (M+H)⁺.

Example 12 (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-Amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoateHydrochloride (26)

Following the procedure of Example 6 and substituting acetyl chloridewith benzoyl chloride in Step 4 and substituting ethyl chloroformatewith isopropyl chloroformate in Step 6 provided the title compound (26)(51% yield over 7 steps) as a white solid. ¹H NMR (400 MHz, CD₃OD): δ1.30 (d, J=6.4 Hz, 3H), 1.35 (d, J=6.4 Hz, 12H), 3.16 (dd, J=14.4, 6.8Hz, 1H), 3.23 (dd, J=14.4, 6.8 Hz, 1H), 4.28 (t, J=6.8 Hz, 1H), 4.31(dd, J=12.4, 6.4 Hz, 1H), 4.48 (dd, J=12.0, 2.8 Hz, 1H), 4.92 (m, 2H),5.33 (m, 1H), 7.19 (dd, J=8.0, 2.0 Hz, 1H), 7.24 (d, J=2.0 Hz, 1H), 7.25(d, J=8.0 Hz, 1H), 7.48 (t, J=7.2 Hz, 2H), 7.60 (t, J=7.2 Hz, 1H), 8.00(m, 2H). MS (ESI) m/z 532.0 (M+H)⁺.

Example 13 (1R)-2-Ethoxycarbonyloxy-1-methylethyl(2S)-2-Amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoateHydrochloride (27)

Following the procedure of Example 6 and substituting acetyl chloridewith ethyl chloroformate in Step 4 and substituting ethyl chloroformatewith isopropyl chloroformate in Step 6 provided the title compound (27)(45% yield over 7 steps) as a thick oil. ¹H NMR (400 MHz, CD₃OD): δ 1.23(d, J=6.4 Hz, 3H), 1.28 (t, J=7.2 Hz, 3H), 1.35 (d, J=6.4 Hz, 6H), 1.37(d, J=6.0 Hz, 6H), 3.24 (m, 2H), 4.09 (dd, J=12.0, 6.8 Hz, 1H), 4.17 (q,J=6.8 Hz, 2H), 4.28 (dd, J=12.0, 2.8 Hz, 1H), 4.37 (t, J=7.2 Hz, 1H),4.93 (m, 2H), 5.22 (m, 1H), 7.24 (dd, J=8.0, 2.4 Hz, 1H), 7.27 (d, J=2.4Hz, 1H), 7.31 (d, J=8.0 Hz, 1H).

Example 14 (1R)-2-Isopropoxycarbonyloxy-1-methylethyl(2S)-2-Amino-3-(3,4-bis(isopropoxycarbonyloxy)phenyl)propanoateHydrochloride (28)

Following the procedure of Example 6 and substituting acetyl chloridewith isopropyl chloroformate in Step 4 and substituting ethylchloroformate with isopropyl chloroformate in Step 6 provided the titlecompound (28) (43% yield over 7 steps) as a thick oil. ¹H NMR (400 MHz,CDCl₃): δ 1.21 (d, J=6.0 Hz, 3H), 1.30 (d, J=6.0 Hz, 3H), 1.31 (d, J=6.0Hz, 3H), 1.37 (d, J=6.4 Hz, 12H), 3.39 (m, 1H), 2.53 (m, 1H), 4.14 (m,2H), 4.39 (m, 1H), 4.86 (m, 1H), 4.95 (m, 2H), 5.16 (m, 1H), 7.25-7.33(m, 3H), 8.82 (br. s, 3H).

Example 15 (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-Amino-3-[3,4-bis(isobutanoyloxy)phenyl]propanoate Hydrochloride(29)

Following the procedure of Example 6 and substituting acetyl chloridewith benzoyl chloride in Step 4 and substituting ethyl chloroformatewith isobutyryl chloride in Step 6 provided the title compound (29) (30%yield over 7 steps) as a white solid. ¹H NMR (400 MHz, CD₃OD): δ 1.27(d, J=7.2 Hz, 6H), 1.28 (d, J=7.2 Hz, 6H), 1.30 (d, J=6.4 Hz, 3H), 2.8(m, 2H), 3.17 (dd, J=14.4, 6.8 Hz, 1H), 3.20 (dd, J=14.4, 6.4 Hz, 1H),4.25 (t, J=6.8 Hz, 1H), 4.31 (dd, J=12.4, 6.4 Hz, 1H), 4.47 (dd, J=12.0,3.2 Hz, 1H), 5.31 (m, 1H), 7.12 (d, J=8.0 Hz, 1H), 7.14 (d, J=2.0 Hz,1H), 7.18 (dd, J=8.0, 2.0 Hz, 1H), 7.47 (t, J=7.2 Hz, 2H), 7.58 (t,J=7.2 Hz, 1H), 8.02 (d, J=7.6 Hz, 2H). MS (ESI) m/z 500.2 (M+H)⁺.

Example 16 (1R)-1-Methyl-2-phenylcarbonyloxyethyl(2S)-2-Amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoateHydrochloride (30)

Following the procedure of Example 6 and substituting acetyl chloridewith benzoyl chloride in Step 4 and substituting ethyl chloroformatewith trimethylacetyl chloride in Step 6, provided the title compound(30) (46% yield over 7 steps) as a white solid. ¹H NMR (400 MHz, CD₃OD):δ 1.30 (d, J=6.4 Hz, 3H), 1.33 (s, 9H), 1.34 (s, 9H), 3.13 (dd, J=14.4,6.8 Hz, 1H), 3.20 (dd, J=14.4, 6.4 Hz, 1H), 4.22 (t, J=6.8 Hz, 1H), 4.32(dd, J=12.4, 6.4 Hz, 1H), 4.49 (dd, J=12.0, 3.2 Hz, 1H), 5.33 (m, 1H),7.10 (d, J=8.0 Hz, 1H), 7.11 (d, J=2.0 Hz, 1H), 7.17 (dd, J=8.0, 2.0 Hz,1H), 7.47 (t, J=7.2 Hz, 2H), 7.58 (t, J=7.2 Hz, 1H), 8.02 (m, 2H). MS(ESI) m/z 528.1 (M+H)⁺.

Example 17 (1R,2R)-2-Acetyloxy-1-methylpropyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (31) Step 1: (1R,2R)-2-Hydroxy-1-methylpropyl(2S)-2-[(tert-Butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(32)

N-Boc-L-DOPA(OBn)₂COOH (21.8 g, 45.8 mmol), (2R,3R)-(−)-2,3-butanediol(5 g, 55 mmol) and dicyclohexylcarbodiimide (DCC) were dissolved inanhydrous dichloromethane. A catalytic amount of4-(dimethylamino)pyridine was added to the solution. The mixture wasstirred at room temperature for 16 hours. After filtration, the filtratewas washed with 10% citric acid, 5% sodium bicarbonate, and brine. Theorganic layer was collected, dried over Na₂SO₄, and concentrated.Chromatography (silica gel, 10% ethyl acetate in hexane) gave 16.7 g(67% yield) of the title compound (32). ¹H NMR (400 MHz, CDCl₃): δ 1.05(d, J=6.4 Hz, 3H), 1.13 (d, J=6.4 Hz, 3H), 1.43 (s, 9H), 2.68 (s, 1H,br), 2.94 (dd, J=14.0, 6.8 Hz, 1H), 2.99 (dd, J=14, 6.8 Hz, 1H), 3.67(m, 1H), 4.34 (dd, 1H, J=13.2, 6.8 Hz, 1H), 4.98 (m, 1H), 5.05 (d, J=6.8Hz, 1H, NH), 5.13 (s, 4H), 6.68 (d, J=8.0 Hz, 1H), 6.79 (s, 1H), 6.85(d, J=8.0 Hz, 1H), 7.26-7.43 (m, 10H).

Step 2: (1R,2R)-2-Acetoxy-1-methylpropyl(2S)-2-[(tert-Butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(33)

Acetyl chloride (0.39 mL, 5.5 mmol) and (1R,2R)-2-hydroxy-1-methylpropyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(32) (2.0 g, 3.6 mmol) were dissolved in 25 mL of anhydrousdichloromethane. A solution of pyridine (0.5 mL, 5.5 mmol) indichloromethane was added dropwise at 0° C. The mixture was stirred atroom temperature for 2 hours. The product was extracted withdichloromethane, washed with 5% NaHCO₃, 10% citric acid, and dried overNa₂SO₄. After concentration and drying under vacuum, the crude product(33) (2.0 g, 95% yield) was isolated and used in the next reactionwithout further purification. ¹H NMR (400 MHz, CDCl₃): δ 1.11 (d, J=6.4Hz, 3H), 1.15 (d, J=6.4 Hz, 3H), 1.43 (s, 9H), 2.05 (s, 3H), 2.95 (dd,J=13.6, 6.4 Hz, 1H), 3.00 (dd, J=13.6, 6.4 Hz, 1H), 4.50 (dd, J=13.6,6.4 Hz, 1H), 4.93 (m, 2H), 4.98 (d, 1H, NH), 5.12 (s, 4H), 6.66 (dd,J=8.0, 2.0 Hz, 1H), 6.77 (d, J=2.0 Hz, 1H), 6.84 (d, J=8.0 Hz, 1H),7.29-7.45 (m, 10H).

Step 3: (1R,2R)-2-Acetoxy-1-methylpropyl(2S)-3-(3,4-Dihydroxyphenyl)-2-[(tert-butoxy)carbonylamino]propanoate(34)

To a solution of (1R,2R)-2-acetoxy-1-methylpropyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(phenylmethoxy)phenyl]propanoate(33) (2.0 g, 3.4 mmol) in 20 mL of methanol, 10% Pd—C (100 mg) pre-mixedwith 10 mL of methanol was added under a nitrogen atmosphere. Thenitrogen was exchanged with hydrogen using the evacuation refill cyclemethod. The mixture was stirred under hydrogen atmosphere at roomtemperature for 4 hours. After filtration and washing with methanol, thefiltrate was concentrated to provide 1.4 g (100% yield) of the titlecompound (34). ¹H NMR (400 MHz, CDCl₃): δ 1.14 (d, J=6.4 Hz, 3H), 1.16(d, J=6.4 Hz, 3H), 1.42 (s, 9H), 2.06 (s, 3H), 2.92 (dd, J=12.8, 6.4 Hz,1H), 2.96 (dd, J=12.8, 6.4 Hz, 1H), 4.46 (dd, J=12.4, 6.4 Hz, 1H), 4.95(m, 2H), 5.05 (d, J=8.8 Hz, 1H, NH), 6.65 (d, J=8.0 Hz, 1H), 6.66 (s,1H), 6.73 (d, J=8.0 Hz, 1H). MS (ESI) nl/z 434.1 (M+Na)⁺ and 410.1(M−H)⁻.

Step 4: (1R,2R)-2-Acetyloxy-1-methylpropyl(2S)-3-[3,4-Bis(ethoxycarbonyloxy)phenyl]-2-[(tert-butoxy)carbonylamino]propanoate(35)

To a mixture of (1R,2R)-2-acetyloxy-1-methylpropyl(2S)-3-(3,4-dihydroxyphenyl)-2-[(tert-butoxy)carbonylamino]propanoate(34) (0.5 g, 1.2 mmol) and ethyl chloroformate (0.3 mL, 3.0 mmol) inanhydrous dichloromethane, triethylamine (0.4 mL, 3.0 mmol) was added at0° C. The reaction mixture was stirred at 0° C. for 1 hour. The solutionwas partitioned between dichloromethane and 10% citric acid and washedwith water. The organic layer was dried over MgSO₄, and concentrated todryness. Chromatography (25% ethyl acetate in hexane) provided the titlecompound (35) (0.6 g, 90% yield) as a white, foamy solid. ¹H NMR (400MHz, CDCl₃): δ 1.11 (d, J=6.4 Hz, 3H), 1.13 (d, J=6.4 Hz, 3H), 1.34 (t,J=7.2 Hz, 3H), 1.35 (t, J=7.2 Hz, 3H), 1.40 (s, 9H), 2.02 (s, 3H), 3.02(dd, J=14.0, 6.8 Hz, 1H), 3.07 (dd, J=14.0, 6.8 Hz, 1H), 4.27 (q, H=7.2Hz, 2H), 4.28 (q, J=7.2 Hz, 2H), 4.51 (dd, J=14.0, 6.8 Hz, 1H), 4.93 (m,2H), 5.03 (d, J=8.4 Hz, 1H, NH), 7.03 (dd, J=8.0, 2.0 Hz, 1H), 7.06 (d,J=2.0 Hz, 1H), 7.16 (d, J=8.0 Hz, 1H). MS (ESI) m/z 578.1 (M+Na)⁺.

Step 5: (1R,2R)-2-Acetyloxy-1-methylpropyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (31)

(1R,2R)-2-Acetyloxy-1-methylpropyl(2S)-3-[3,4-bis(ethoxycarbonyloxy)phenyl]-2-[(tert-butoxy)carbonylamino]propanoate(35) (0.6 g, 1.1 mmol) was dissolved in 10 mL of 4M HCl in 1,4-dioxane.The mixture was stirred at room temperature for 60 min. Dioxane wasevaporated under reduced pressure. The colorless oil was further driedunder vacuum to give 0.6 g (96% yield) of the title compound (31). ¹HNMR (400 MHz, CD₃OD): δ 1.16 (d, J=7.8 Hz, 3H), 1.18 (d, J=7.8 Hz, 3H),1.35 (t, J=7.2 Hz, 3H), 1.36 (t, J=7.2 Hz, 3H), 2.03 (s, 3H), 3.23 (dd,J=14.0, 6.8 Hz, 1H), 3.27 (dd, J=14.0, 6.8 Hz, 1H), 4.28 (q, J=7.2 Hz,2H), 4.30 (q, J=7.2 Hz, 2H), 4.40 (t, J=6.8 Hz, 1H), 4.94 (m, 1H), 5.05(m, 1H), 7.26 (dd, J=8.0, 2.0 Hz, 1H), 7.30 (d, J=2.0 Hz, 1H), 7.33 (d,J=8.0 Hz, 1H). MS (ESI) m/z 456.2 (M+H)⁺ and 454.0 (M−H)⁻.

Example 18 (1R,2R)-1-Methyl-2-(2-methylpropanoyloxy)propyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (36)

Following the procedure of Example 17 and substituting acetyl chloridewith iso-butyryl chloride in Step 2 provided the title compound (36)(42% yield over 5 steps) as a colorless oil. ¹H NMR (400 MHz, CD₃OD): δ1.15 (d, J=7.2 Hz, 3H), 1.16 (d, J=6.8 Hz, 3H), 1.17 (d, J=6.8 Hz, 3H),1.18 (d, J=6.0 Hz, 3H), 1.36 (t, J=7.2 Hz, 3H), 1.37 (t, J=7.2 Hz, 3H),2.56 (m, 1H), 3.22 (dd, J=14.4, 7.2 Hz, 1H), 3.26 (dd, J=14.4, 7.2 Hz,1H), 4.30 (q, J=7.2 Hz, 2H), 4.31 (q, J=7.2 Hz, 2H), 4.39 (t, J=7.2 Hz,1H), 4.96 (m. 1H), 5.19 (m, 1H), 7.25 (dd, J=8.0, 2.0 Hz, 1H), 7.30 (d,J=2.0 Hz, 1H), 7.32 (d, J=8.0 Hz, 1H). MS (ESI) m/z 484.1 (M+H)⁺.

Example 19 (1R,2R)-2-Isobutoxycarbonyloxy-1-methylpropyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (37)

Following the procedure of Example 17 and substituting acetyl chloridewith isobutyl chloroformate in Step 2 provided the title compound (37)(30% yield over 5 steps) as a colorless oil. ¹H NMR (400 MHz, CD₃OD): δ0.97 (d, J=6.4 Hz, 6H), 1.22 (d, J=6.8 Hz, 3H), 1.25 (d, J=6.4 Hz, 3H),1.371 (t, J=6.8 Hz, 3H), 1.375 (t, J=7.2 Hz, 3H), 1.97 (hept. J=6.8 Hz,1H), 3.21 (dd, J=14.4, 7.6 Hz, 1H), 7.30 (dd, J=14.4, 7.2 Hz, 1H), 3.91(dd, J=10.4, 6.8 Hz, 1H), 3.95 (dd, J=10.4, 6.8 Hz, 1H), 4.31 (m, 4H),4.40 (t, J=7.6 Hz, 1H), 4.81 (m, 1H), 5.09 (m, 1H), 7.27 (dd, J=8.0, 2.4Hz, 1H), 7.31 (d, J=2.4 Hz, 1H), 7.33 (d, J=8.0 Hz, 1H).

Example 20 (1R,2R)-2-Isopropoxycarbonyloxy-1-methylpropyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (38)

Following the procedure of Example 17 and substituting acetyl chloridewith isopropyl chloroformate in Step 2 provided the title compound (38)(33% yield over 5 steps) as a colorless oil. ¹H NMR (400 MHz, CD₃OD): δ1.21 (d, J=6.4 Hz, 3H), 1.24 (d, J=6.8 Hz, 3H), 1.29 (d, J=6.4 Hz, 3H),1.37 (t, J=6.8 Hz, 3H), 1.38 (t, J=6.8 Hz, 3H), 3.19-3.29 (m, 2H), 4.31(m, 4H), 4.40 (t, J=7.2 Hz, 1H), 4.79-4.87 (m, 2H), 5/08 (m, 1H), 7.27(dd, J=8.0, 2.0 Hz, 1H), 7.31 (d, J=2.0 Hz, 1H), 7.34 (d, J=8.0 Hz, 1H).

Example 21 (1R,2R)-1-Methyl-2-pentyloxycarbonyloxypropyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (39)

Following the procedure of Example 17 and substituting acetyl chloridewith pentyl chloroformate in Step 2 provided the title compound (39)(36% yield over 5 steps) as a colorless oil. ¹H NMR (400 MHz, CDCl₃): δ0.90 (t, J=7.0, 3H), 1.16 (d, J=6.8 Hz, 3H), 1.20 (d, J=6.4 Hz, 3H),1.33-1.38 (m, 10H), 1.66 (m, 2H), 3.36 (dd, J=14.0, 6.8 Hz, 1H), 3.50(dd, J=14.0, 4.8 Hz, 1H), 4.092 (m, 2H), 4.27 (m, 4H), 4.37 (br. s, 1H),4.80 (m, 1H), 5.03 (m, 1H), 7.22-7.31 (m, 3H), 8.82 (br. s, 3H).

Example 22 (1R,2R)-2-Hexyloxycarbonyloxy-1-methylpropyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (40)

Following the procedure of Example 17 and substituting acetyl chloridewith hexyl chloroformate in Step 2 provided the title compound (40) (32%yield over 5 steps) as a colorless oil. ¹H NMR (400 MHz, CDCl₃): δ 0.81(t, J=7.0, 3H), 1.07 (d, J=6.4 Hz, 3H), 1.11 (d, J=6.4 Hz, 3H), 1.28 (m,12H), 1.57 (m, 2H), 3.28 (m, 1H), 3.42 (m, 1H), 4.01 (t, J=6.4 Hz, 2H),4.20 (m, 4H), 4.31 (br. s, 1H), 4.72 (m, 1H), 4.94 (m, 1H), 7.14-7.23(m, 3H), 8.74 (br. s, 3H).

Example 23 (1R,2R)-2-Acetoxy-1-methylpropyl(2S)-2-Amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoateHydrochloride (41)

Following the procedure of Example 17 and substituting ethylchloroformate with iso-propyl chloroformate in Step 4 provided the titlecompound (41) (63% yield over 5 steps) as a colorless oil. ¹H NMR (400MHz, CD₃OD): δ 1.17 (d, J=6.0 Hz, 3H), 1.18 (d, J=6.0 Hz, 3H), 1.35 (d,J=6.0 Hz, 6H), 1.37 (d, J=6.0 Hz, 6H), 2.04 (s, 3H), 3.21 (dd, J=14.8,7.6 Hz, 1H), 3.27 (dd, J=14.4, 7.2 Hz, 1H), 4.40 (t, J=7.6 Hz, 1H), 4.93(m, 3H), 5.05 (m, 1H), 7.25 (dd, J=8.0, 2.0 Hz, 1H), 7.28 (d, J=2.0 Hz,1H), 7.31 (d, J=8.0 Hz, 1H). MS (ESI) m/z 484.2 (M+H)⁺ and 482.1 (M−H)⁻.

Example 24 (1R,2R)-1-Methyl-2-(2-methylpropanoyloxy)propyl(2S)-2-Amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoateHydrochloride (42)

Following the procedure of Example 17 and substituting acetyl chloridewith iso-butyryl chloride in Step 2 and substituting ethyl chloroformatewith iso-propyl chloroformate in Step 4, provided the title compound(42) (12% yield over 5 steps) as a colorless oil. ¹H NMR (400 MHz,CD₃OD): δ 1.15 (d, J=7.2 Hz, 3H), 1.16 (d, J=7.2 Hz, 3H), δ 1.17 (d,J=6.0 Hz, 3H), 1.18 (d, J=6.0 Hz, 3H), 1.36 (d, J=6.0 Hz, 6H), 1.37 (d,J=6.0 Hz, 6H), 2.56 (m, 1H), 3.21 (dd, J=14.4, 7.2 Hz, 1H), 3.26 (dd,J=14.4, 7.2 Hz, 1H), 4.40 (t, J=7.2 Hz, 1H), 4.95 (m, 3H), 5.05 (m, 1H),7.24 (dd, J=8.0, 2.0 Hz, 1H), 7.28 (d, J=2.0 Hz, 1H), 7.32 (d, J=8.0 Hz,1H). MS (ESI) m/z 512.2 (M+H)⁺.

Example 25 (2R)-2-Acetyloxypropyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (43) Step 1:(2R)-1-(tert-Butyldimethyl-1-silyloxy)propan-2-ol (44)

Imidazole (6.9 g, 100.0 mmol) was added to a solution of (R)-(−)-1,2propanediol (15.2 g, 100.0 mmol) and tert-butyl dimethylsilyl chloridein 500 mL of tetrahydrofuran and the mixture was stirred at roomtemperature for two hours. The reaction mixture was concentrated to asmall volume, diluted with ethyl acetate (300 mL), washed with saturatedaqueous NaHCO₃, brined, dried over Na₂SO₄, and concentrated to an oil ofthe title compound (44) (35.2 g, 92.6% yield). ¹H NMR (400 MHz, CDCl₃):δ 0.00 (s, 6H), 0.83 (s, 9H), 1.03 (d, J=6.0 Hz, 3H), 2.38 (s, 1H, br.),3.25 (dd, J=8.0, 7.6 Hz, 1H), 3.25 (dd, J=9.6, 3.2 Hz, 1H), 3.73 (m,1H).

Step 2: (1R)-1-Methyl-2-(tert-butyldimethyl-1-silyloxy)ethyl Acetate(45)

Acetyl chloride (5.0 mL, 70.5 mmol) was added to a solution of(2R)-1-(tert-butyldimethyl-1-silyloxy)propan-2-ol (44) (9.0 g, 47.0mmol) and pyridine (50 mL) in 300 mL of dichloromethane at 0° C. Afterstirring at room temperature for three hours, the solution was washedwith 10% aqueous citric acid (3×100 mL), brined, dried over Na₂SO₄, andconcentrated to an oil of the title compound (45) 10.8 g (98.1% yield).¹H NMR (400 MHz, CDCl₃): δ 0.06 (s, 6H), 0.89 (s, 9H), 1.20 (d, J=6.4Hz, 3H), 2.04 (s, 3H), 3.60 (m, 2H), 4.92 (m 1H).

Step 3: (1R)-2-Bromomethylethyl Acetate (46)

(1R)-1-Methyl-2-(tert-butyldimethyl-1-silyloxy)ethyl acetate (45) (2.32g, 17 mmol) was added to a 50-mL dichloromethane solution of PPh₃Br₂(7.36 g, 17 mmol) at 0° C. After stirring at room temperature for threehours, the solution was filtered, concentrated to a small volume,diluted with ethyl acetate (300 mL), washed with saturated aqueousNaHCO₃ (3×150 mL), brined, dried over Na₂SO₄, and concentrated toprovide 2.6 g of the title compound (46) as a crude oil (69% yield). ¹HNMR (400 MHz, CDCl₃): δ 1.25 (d, J=6.4 Hz, 3H), 1.98 (s, 3H), 3.34 (m,2H), 4.95 (m 1H).

Step 4: (2R)-2-Acetyloxypropyl(2S)-3-(3,4-Dihydroxyphenyl)-2-[(tert-butoxy)carbonylamino]propanoate(47)

A solution of Boc-L-Dopa tetrabutyl ammonium salt (5.6 g, 104.0 mmol)and crude (1R)-2-bromomethylethyl acetate (46) (2.6 g, 11.6 mmol) in50-mL dimethylacetamide was stirred overnight at 65° C. The reactionmixture was diluted with methyl tert-butyl ether (500 mL), washed withsaturated aqueous NaHCO₃ (3×250 mL), brined, dried over Na₂SO₄, andconcentrated to an oil. Chromatography eluting with EtOAc/hexane (2:3)gave 1.5 g (36.7% yield) of the title compound (47). ¹H NMR (400 MHz,CDCl₃): δ 1.23 (d, J=6.8 Hz, 3H), 1.43 (s, 9H), 2.10 (s, 3H), 2.98 (m,2H), 4.02 (dd, J=7.2, 6.8 Hz, 1H), 4.30 (dd, J=6.8, 2.8 Hz, 1H), 4.54(m, 1H), 4.97 (d, 1H, NH), 5.10 (m, 1H). MS (ESI) m/z 398.1 (M+H)⁺ and396.1 (M−H)⁻.

Step 5: (2R)-2-Acetyloxypropyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (43)

To a mixture of (2R)-2-acetyloxypropyl(2S)-3-(3,4-dihydroxyphenyl)-2-[(tert-butoxy)carbonylamino]propanoate(47) (0.3 g, 0.7 mmol) and ethyl chloroformate (0.2 mL, 2.0 mmol) inanhydrous dichloromethane, a solution of triethylamine (0.4 mL, 3.0mmol) in dichloromethane was added at 0° C. The reaction mixture wasstirred at room temperature for 1 hour. The resulting solution waspartitioned between dichloromethane and 10% citric acid and washed withwater. The organic layer was dried over MgSO₄, and concentrated todryness. Chromatography (30% ethyl acetate in hexane) provided an oil(0.2 g). The oil was dissolved in a solution of HCl/1,4-dioxane (10 mL)and stirred at room temperature for one hour. Dioxane was removed underreduced pressure to provide the title compound (43) (0.1 g, 41.4% yield)as an oil. ¹H NMR (400 MHz, CD₃OD): δ 1.24 (d, J=6.8 Hz, 3H), 1.36 (t,J=7.2 Hz, 3H), 1.37 (t, J=7.2 Hz, 3H), 2.04 (s, 3H), 3.20 (dd, J=14.4,7.2 Hz, 1H), 3.32 (dd, J=14.4, 7.2 Hz, 1H), 4.21 (dd, J=12, 6.8 Hz, 1H),4.30 (q, J=7.2 Hz, 2H), 4.31 (q, J=7.2 Hz, 2H), 4.40 (dd, J=12.0, 7.2Hz, 1H), 4.42 (t, J=7.2 Hz, 1H), 5.11 (m, 1H), 7.25 (dd, J=8.0, 2.0 Hz,1H), 7.28 (d, J=2.0 Hz, 1H), 7.33 (d, J=8.0 Hz, 1H). MS (ESI) m/z 442.2(M+H)⁺.

Example 26 (2R)-2-Acetyloxypropyl(2S)-2-Amino-3-[3,4-bis(methylethoxycarbonyloxy)phenyl]propanoateHydrochloride (48)

Following the procedure of Example 25 and substituting ethylchloroformate with iso-propyl chloroformate in Step 5, provided thetitle compound (48) (19% yield over 5 steps) as a colorless oil. ¹H NMR(400 MHz, CD₃OD): δ 1.25 (d, J=6.8 Hz, 3H), 1.36 (d, J=6.4 Hz, 6H), 1.36(d, J=6.4 Hz, 6H), 2.04 (s, 3H), 3.19 (dd, J=14.4, 7.6 Hz, 1H), 3.25(dd, J=14.4, 7.7 Hz, 1H), 4.21 (dd, J=12.0, 7.2 Hz, 1H), 4.40 (dd,J=12.0, 3.2 Hz, 1H), 4.43 (t, J=7.6 Hz, 1H), 4.93 (m, 2H), 5.12 (m, 1H),7.24 (dd, J=8.0, 2.0 Hz, 1H), 7.27 (d, J=2.0 Hz, 1H), 7.32 (d, J=8.0 Hz,1H). MS (ESI) m/z 470.2 (M+H)⁺ and 468.1 (M−H)⁻.

Example 27 (2R)-2-Phenylcarbonyloxypropyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoateHydrochloride (49)

Following the procedure of Example 25 and substituting acetyl chloridewith benzoyl chloride in Step 2 provided the title compound (49) (52%yield over 5 steps) as a colorless oil. ¹H NMR (400 MHz, CD₃OD): δ 1.36(t, J=7.2 Hz, 6H), 1.39 (d, J=6.8 Hz, 6H), 3.18 (dd, J=14.4, 7.2 Hz,1H), 3.27 (dd, J=14.4, 7.2 Hz, 1H), 4.29 (q, J=7.2 Hz, 4H), 4.39 (dd,J=12.8, 6.4 Hz, 1H), 4.41 (t, J=6.8 Hz, 1H), 4.52 (dd, J=12.0, 3.2 Hz,1H), 5.39 (m, 1H), 7.16 (dd, J=8.0, 2.0 Hz, 1H), 7.23 (d, J=2.0 Hz, 1H),7.26 (d, 1H, J=8.0 Hz, 1H), 7.47 (t, J=8.0 Hz, 2H), 7.61 (t, J=8.0 Hz,1H), 8.01 (m, 2H). MS (ESI) m/z 504.2 (M+H)⁺.

Example 28 (2R)-2-Phenylcarbonyloxypropyl(2S)-2-Amino-3-(3,4-bis(methylethoxycarbonyloxy)phenyl]propanoateHydrochloride (50)

Following the procedure of Example 25 and substituting acetyl chloridewith benzoyl chloride in Step 2 and substituting ethyl chloroformatewith iso-propyl chloroformate in Step 5 provided the title compound (50)(41% yield over 5 steps) as a colorless oil. ¹H NMR (400 MHz, CD₃OD): δ1.35 (d, J=6.8 Hz, 6H), 1.36 (d, J=6.8 Hz, 6H), 1.39 (d, J=6.8 Hz, 3H),3.19 (dd, J=14.4, 7.6 Hz, 1H), 3.27 (dd, J=14.4, 6.8 Hz, 1H), 4.39 (dd,J=14.4, 6.8 Hz, 1H), 4.41 (t, J=6.8 Hz, 1H), 4.54 (dd, J=14.4, 3.2 Hz,1H), 4.92 (m, 2H), 5.39 (m, 1H), 7.21 (dd, J=8.0, 2.0 Hz, 1H), 7.23 (d,J=2.0 Hz, 1H), 7.24 (d, J=8.0 Hz, 1H), 7.47 (t, J=8.0 Hz, 2H), 7.60 (t,J=8.0 Hz, 1H), 8.01 (m, 2H). MS (ESI) m/z 532.1 (M+H)⁺.

Example 29 Crystallization of (1R)-2-Acetyloxy-1-methylethyl(2S)-2-Amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate HydrogenFumarate (21)

(1R)-2-Acetyloxy-1-methylethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate hydrogenfumarate (21) was crystallized using the solvents listed in Table 1 on a100 mg scale. Differential scanning calorimetry (DCS) and X-ray powderdiffraction (XRPD) analyses indicated that crystalline(1R)-2-acetyloxy-1-methylethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate hydrogenfumarate salt prepared using these solvents are the same polymorph.

TABLE 1 Properties of crystalline (1R)-2-acetyloxy-1-methylethyl(2S)-2-amino-3-[3,4- bis(ethoxycarbonyloxy)phenyl]propanoate hydrogenfumarate (21) crystallized from various solvents. Melting peak Hygro-XRPD Solvents m.p. (° C.) on DSC (° C.) ΔH (g/J) scopicity 2θ (deg)Ethyl acetate 78.1-80.7 82.05 102 None 4.0, 12.6, 13.7, 15.1, 16.5, 22,24 Ethyl acetate- 78.9-81.5 82.23 104 None 4.0, 12.6, diisopropyl ether13.7, 15.1, 16.5, 22, 24 Ethyl acetate- 79.4-81.3 80.28 119 None 4.0,12.6, methyl tert-butyl 13.7, 15.1, ether 16.5, 22, 24 Acetonitrile-78.6-79.9 80.68 110 None 4.0, 12.6, methyl tert-butyl 13.7, 15.1, ether16.5, 22, 24

Example 30 Intracolonic Bioavailability of Levodopa Prodrugs in Rats

Sustained release oral dosage forms, which release therapeutic agentsslowly over periods of about 6 to about 24 hours, generally release asignificant proportion of the dose within the colon. Thus, therapeuticagents suitable for use in sustained release dosage forms should becolonically absorbed. This experiment was conducted to assess the uptakeand resultant plasma/blood levels of levodopa, following intracolonicadministration of a compound of Formula (I) with co-administration ofcarbidopa (intraperitoneally), and thereby determine the suitability ofa compound of Formula (I) for use in an oral sustained release dosageform. Bioavailability of levodopa following co-administration of acompound of Formula (I) and carbidopa was calculated relative tointracolonic administration of levodopa and co-administration ofcarbidopa (i.p.).

Levodopa was obtained from Sigma-Aldrich (St. Louis, Mo.). Carbidopa wasobtained from Spectrum Laboratory Products (Gardena, Calif.). Levodopahydrochloride salt and levodopa prodrugs of Formula (I) were synthesizedfrom commercial levodopa as described in Examples 1-29. For intracolonicadministration, levodopa HCl salt was dissolved in water and levodopaprodrugs were dissolved in sodium phosphate buffer at pH 6.2 orsuspended in 0.5% methylcellulose/0.1% Tween 80 in sodium phosphatebuffer at pH 7.02.

Male Sprague-Dawley rats (approx. 250 g) with indwelling jugular veincannulas were obtained from Charles River (Hollister, Calif.). Rats wereadditionally cannulated in the colon just distal to the cecum. Allanimals were allowed 48 h to recover from surgery prior to shipping andwere acclimated for at least 48 h prior to study. Rats were fastedovernight and for the first 4 hours of the study. Water was provided adlibitum.

Two groups of male Sprague-Dawley rats (4-6 rats/group) receivedintravenous bolus injections of levodopa HCl salt or levodopa prodrug at10 mg-eq levodopa/kg. To determine colonic absorption of levodopa andlevodopa prodrugs, four different groups of rats were dosed withlevodopa HCl salt at 75 mg-eq levodopa/kg or levodopa prodrug at 25mg-eq levodopa/kg. In the studies, carbidopa (administered as carbidopamonohydrate or carbidopa HCl salt) was co-administered intraperitoneallyat 10 mg-eq carbidopa/kg with levodopa or levodopa prodrug. Bloodsamples were obtained at intervals up to 24 hours post-dosing. All bloodsamples were subsequently analyzed for intact prodrug and/or levodopausing LC-MS/MS.

Quenched blood samples were frozen and stored at −80° C. prior toanalysis. Samples were analyzed by a sensitive and specific LC-MS/MSmethod for simultaneous determination of levodopa prodrug and levodopa.The lower limits of quantitation for levodopa was in the range of about0.004 μg/mL to about 0.02 μg/mL and the upper limit of quantitation wasin the range of about 5 μg/mL to about 15 μg/mL.

Concentration data for levodopa and levodopa prodrug in blood wereanalyzed by noncompartmental methods using WinNonlin™ Software (Version3.3. Pharsight Corp., Mountain View, Calif.). Non-compartmental analysiswas performed on individual profiles. All concentration values below thelimit of quantitation (BLQ) were treated as 0 (zero) for thepharmacokinetic analysis. Low concentration values at predose weretreated as BLQ. Nominal sample collection time points were used for thecalculation of pharmacokinetic parameters. All concentration data wereplotted using SigmaPlot™ (Version 9.0, Systat Software Inc., PointRichmond, Calif.).

The maximum concentration (C_(max)) and time to C_(max) (T_(max)) wereobtained by observation. The apparent elimination half-life (T_(1/2))was obtained by linear regression of three or more log-transformed datapoints in the terminal phase. The area under the concentration versustime curve (AUC) was obtained by the linear trapezoidal method usingconcentration data over the dosing interval. The AUC value extrapolatedto infinity (AUC_(inf)) was calculated as

AUC _(inf) =AUC _((0-tlast)) +C _(last)/λ_(z)

where t_(last) is the time of the last quantifiable concentration(C_(last)) and λ_(z) is the rate constant of the apparent terminalelimination phase.

The bioavailability (F) of levodopa after extravascular dosing oflevodopa or prodrug was calculated by comparison to data followingintravenous administration of levodopa as follows:

F(%)=100×(AUC _(ex)/Dose_(ex))/(AUC _(i.v.)/Dose_(i.v.))

where AUC_(ex) is the area under the levodopa concentration versus timecurve in μg·hr/mL following extravascular administration of levodopa orprodrug; Dose_(ex) is the extravascular dose expressed in mg-equivalentsof levodopa/kg body weight; AUC_(i.v.) is the area under the levodopaconcentration versus time curve in μg·hr/mL following intravenousadministration of levodopa; Dose_(i.v.) is the intravenous doseexpressed in mg-equivalents of levodopa/kg body weight.

Intracolonic administration of levodopa and intraperitonealadministration of carbidopa to rats results in very low relative colonicbioavailability of levodopa (i.e., only 3.4% of intracolonicallyadministered levodopa). By comparison, intracolonic administration of acompound of Formula (I) with intraperitoneal administration of carbidopaexhibited improved relative intracolonic bioavailability of levodopa byat least 2-fold. For example, the intracolonic bioavailability oflevodopa following intracolonic administration of compounds (14), (21),(22), (23), (31), (36), (38), and (43) at 25 mg-eq/kg of levodopa andintraperitoneal administration of carbidopa at 10 mg-eq/kg to ratsprovided an intracolonic bioavailability of levodopa that was at least 3times greater than the intracolonic bioavailability of an equivalentdose of levodopa itself. The data demonstrates that certain levodopaprodrugs can be formulated as compositions suitable for effectivesustained oral release and uptake of a compound of Formula (I) and/orlevodopa from the colon.

Example 31 Intracolonic Bioavailability of Levodopa Prodrugs in Monkeys

Male Cynomologous monkeys weighing about 3.0 kg were used in thestudies. Monkeys are fasted overnight prior to the study until 4 hoursafter dosing. Water was provided ad libitum.

Carbidopa was prepared as a solution (0.72 mg/mL) in sodium acetatebuffer pH 5.16. Levodopa prodrug (21) was prepared as a suspension (19.1mg/mL) in 0.5% methyl cellulose/0.1% Tween-80 in NaH₂PO₄ pH 7.02.

Carbidopa (5 mL/kg; 3.33 mg-eq carbdopa/kg) was administered IP to 4monkeys, and levodopa prodrug (21) (1 mL/kg; 10 mg-eq levodopa/kg) wasadministered intracolonically to 4 monkeys. Blood samples were collectedat pre-dose and at 0.17, 0.25, 0.5, 0.75, 1, 2, 4, 6, 8, 12, and 24hours post-dose. About 0.3 mL of blood was collected in pre-chilledK₂EDTA tubes containing 100 μL of 10% sodium metabisulfite. The contentswere gently vortexed at low speed to ensure that the sampled blood cameinto contact with sodium metabisulfite while maintaining ice on thesamples at all times. About 0.1 mL of the anticoagulated blood was addedto each of 2 pre-chilled cryovials that each contained about 0.3 mL ofquenching media (89.3% v/v methanol and 10.7% v/v 4N perchloric acid)within 5 minutes of bleed. Within 30 minutes of blood collection, thesamples were centrifuged at about 3,000 rpm, 4° C., for 10 min. Thesamples were then stored at −70° C.

Blood samples were analyzed as described in Example 30. Pharmacokineticparameters for levodopa following intracolonic administration oflevodopa prodrug (21) is shown in Table 2.

TABLE 2 Mean (SD) pharmacokinetic parameters for levodopa followingintracolonic administration of levodopa prodrug (21). C_(max) T_(max)T_(1/2−λ) AUC_(t) AUC_(inf) Fic^(†) (μg/mL) (h) (h) (μg · h/mL) (μg ·h/mL) (%) Mean (SD) 0.76 (0.12) 0.42 (0.14) 0.50 (0.16) 0.81 (0.21) 0.45(0.24) 11.4 (3.2) ^(†)Fic = bioavailability relative to levodopa IV, 5mg-eq levodopa/kg IV and 10 mg-eq carbidopa IP, mean AUCinf value of3.69 μg · h/mL.

Example 32 Use of Clinical Trials to Assess the Efficacy of Compounds ofFormula (I) in Treating Parkinson's Disease

The following clinical study may be used to assess the efficacy of acompound of Formula (I) in treating Parkinson's disease.

Patients with idiopathic PD fulfilling the Queen Square Brain Bankcriteria (Gibb et al., J Neurol Neurosurg Psychiatry 1988, 51, 745-752)with motor fluctuations and a defined short duration levodopa response(1.5-4 hours) are eligible for inclusion. Clinically relevant peak dosedyskinesias following each morning dose of their current medication area further pre-requisite. Patients are also required to have been stableon a fixed dose of treatment for a period of at least one month prior tostarting the study. Patients are excluded if their current drug regimeincludes slow-release formulations of levodopa, COMT inhibitors,selegiline, anticholinergic drugs, or other drugs that could potentiallyinterfere with gastric absorption (e.g. antacids). Other exclusioncriteria include patients with psychotic symptoms or those onantipsychotic treatment patients with clinically relevant cognitiveimpairment, defined as MMS (Mini Mental State) score of less than 24(Folstein et al., J Psychiatr Res 1975,12, 189-198), risk of pregnancy,Hoehn & Yahr stage 5 in off-status, severe, unstable diabetes mellitus,and medical conditions such as unstable cardiovascular disease ormoderate to severe renal or hepatic impairment. Full blood count, liver,and renal function blood tests are taken at baseline and aftercompletion of the study.

A randomized, double-blind, and cross-over study design is used. Eachpatient is randomized to the order in which either levodopa, placebo, ortest compound is administered in a single-dose challenge in double-dummyfashion in three consecutive sessions.

Patients are admitted to a hospital for an overnight stay prior toadministration of a compound of Formula (I) the next morning on threeseparate occasions at weekly intervals. After withdrawal of allanti-parkinsonian medication from midnight the previous day a compoundof Formula (I) is administered at exactly the same time in the morningin each patient under fasting conditions.

Patients are randomized to the order of the days on which they receiveplacebo or a compound of Formula (I). The pharmacokinetics of a compoundof Formula (I) is assessed by monitoring the plasma levodopaconcentration over time. Prior to administration, a 22 G intravenouscatheter is inserted in a patient's forearm. Blood samples of 5 mL eachare taken at baseline and 15, 30, 45, 60, 75, 90, 105, 120, 140, 160,180, 210, and 240 minutes after administering compound of Formula (I) oruntil a full off-state has been reached if this occurs earlier than 240minutes after drug ingestion. Samples are centrifuged immediately at theend of each assessment and stored deep frozen until assayed. Plasmalevodopa, prodrug, and 3-O-methyl-dopa levels are assessed byhigh-pressure liquid chromatography (HPLC). On the last assessmentadditional blood may be drawn for routine hematology, blood sugar,liver, and renal function.

For clinical assessment, motor function is assessed using UPDRS (UnitedParkinson's Disease Rating Scale) motor score and BrainTest (Giovanni etal., J Neurol Neurosurg Psychiatry 1999, 67, 624-629.), which is atapping test performed with the patient's more affected hand on thekeyboard of a laptop computer. These tests are carried out at baselineand then immediately following each blood sample until patients reachtheir full on-stage, and thereafter at 3 intervals of 20 min, and 30 minintervals until patients reach their baseline off-status. Once patientsreach their full on-state, video recordings are performed three times at20 min intervals. The following mental and motor tasks, which have beenshown to increase dyskinesia (Duriff et al., Mov Disord 1999,14,242-245) are monitored during each video session: (1) sitting still for1 minute; (2) performing mental calculations; (3) putting on andbuttoning a coat; (4) picking up and drinking from a cup of water; and(5) walking. Videotapes are scored using, for example, versions of theGoetz Rating Scale and the Abnormal Involuntary Movements Scale todocument a possible increase in test compound induced dyskinesia.

Actual occurrence and severity of dyskinesia is measured with aDyskinesia Monitor (Manson et al., J Neurol Neurosurg Psychiatry 2000,68, 196-201). The device is taped to a patient's shoulder on their moreaffected side. The monitor records during the entire time of achallenging session and provides a measure of the frequency and severityof occurring dyskinesias.

Results may be analyzed using appropriate statistical methods.

Example 33 Administration of a Compound of Formula (I) for the Treatmentof Restless Legs Syndrome

A placebo-controlled, cross-over clinical trial is conducted to assessthe effects of a compound of Formula (I) on sensory and motor symptomsin patients with restless legs syndrome (Garcia-Borreguero et al.,Neurology 2002,11(2), 1573-79). Briefly, twenty patients with RLS(either idiopathic or secondary) are randomized and treated for 6 weekswith either the prodrug or placebo. A compound of Formula (I) isformulated as osmotic sustained release capsules containing atherapeutically effective amount of prodrug (preparation of thesustained release capsules is described in Section 5.1 above) and isadministered as appropriate. After a 1-week washout, the patients arecrossed over to alternative treatment for 6 weeks. Patients are rated atbaseline and at scheduled intervals by the RLS Rating Scale, ClinicalGlobal Impression, pain analog scale, and Pittsburgh Sleep QualityIndex. In addition, all-night polysomnography is performed before andafter the drug treatment periods (Foldvary-Schaefer et al., Epilepsia2002, 43(12), 1493-1497). A positive result for a compound of Formula(I) is associated with reduced symptoms on all rating scales whencompared with the placebo.

Example 34 Animal Model for Assessing Therapeutic Efficacy of LevodopaProdrugs for Treating Tardive Dyskinesia

Vacuous chewing movements (VCM) are a rodent model of tardive dyskinesia(Andreassen et al., Br J Pharmacol 1996,119(4), 751-7; and Shoham etal., Brain Res 2004, 1004(1-2), 142-147). In this model, animals aretreated chronically with antipsychotics and their vacuous chewingmotions are assessed by observation. The model has been shown to besensitive to differential effects of typical and atypical antipsychoticsand potential anti-dyskinetic agents.

Rats are housed in a controlled environment and allowed to acclimatizeprior to testing. In order to limit neuroleptic-induced weight gain,food consumption is restricted to 15 g per animal per day. Rats areweighed biweekly throughout the study.

For two weeks prior to administration of test compound, animals arehandled daily and habituated to the animal colony and the proceduresrelated to drug administration and video recording. Subsequently (week0), rats undergo a behavior video recording session following which theyare randomized to a haloperidol treatment and a control group. The ratsin the treatment group receive an intramuscular injection in the thighmuscles with haloperidol decanoate. The control rats are similarlyinjected with an equal volume of phosphate buffered saline (PBS). Thehaloperidol decanoate and saline injections are repeated every fourweeks, for 20 weeks. Additional behavior video recording sessions areperformed at weeks 12, 20 and 24 (i.e., 4 weeks after the last (fifth)injection). During the injection procedures, rats are handheld withminimal restraint.

On the basis of the results of the behavior assessment performed 24weeks after the first haloperidol injection (i.e., baseline day), thehaloperidol-treated rats are assigned to 10 subject-each treatmentgroups having an equal mean frequency of observed VCM episodes. One weeklater (i.e., test day), the groups are randomized to receive oneintraperitoneal injection with either vehicle or levodopa prodrug in thevehicle. Rats undergo a 30-150 min video recorded behavior assessmentsession following the injection. Two weeks after the test day (i.e.,post-test day), the video recorded behavior assessment session isrepeated to investigate longer-term effects of the experimentaltreatments.

The videotapes are scored. A VCM episode is defined as a bout ofvertical deflections of the lower jaw, which may be accompanied bycontractions of the jaw musculature.

Example 35 Animal Model for Assessing Therapeutic Efficacy for TreatingSchizophrenia Morris Water Maze

The Morris Water Maze (MWM) is used as a well-validated hippocampusdependent test of visual-spatial memory. The MWM tests the ability of ananimal to locate a hidden platform submerged under water by usingextra-maze cues from the test environment. Rats are trained in a pool1.8 m in diameter and 0.6 m high, containing water at about 26° C. A 10cm square transparent platform is hidden in a constant position 1 cmbelow the water level in the pool. Only distal visuo-spatial cues areavailable to the rats for location of the submerged platform. The ratsare given trials to find the hidden platform. The escape latency, i.e.,the time required by the rats to find and climb onto the platform, isrecorded for up to 120 s. Each rat is allowed to remain on the platformfor 30 s, after which it is removed to its home cage. If the rat did notfind the platform within 120 s, it is manually placed on the platformand returned to its home cage after 30 s.

Male Sprague-Dawley rats weighing 150-200 g are used. Ten days beforethe beginning of the experiments, the rats are handled once daily toreduce experimental stress. A composition provided by the presentdisclosure or control is administered to the rats for three consecutivedays before behavioral testing. On each day of behavioral testing therats are injected with either haloperidol or saline 30 min beforebehavioral assessment.

PCP-Induced Hyperactivity Model

Male C57B1/6J mice are used. Mice are received at 6-weeks of age. Uponreceipt, mice are assigned unique identification numbers (tail marked)and are group housed with 4 mice/cage in ventilated cages. All animalsremain housed in groups of four during the study. All mice areacclimated to the colony room for at least two weeks prior to testingand are subsequently tested at an average age of 8 weeks of age. Duringthe period of acclimation, mice and rats are examined on a regularbasis, handled, and weighed to assure adequate health and suitability.Animals are maintained on a 12/12 light/dark cycle. The room temperatureis maintained between 20° C. and 23° C. with a relative humiditymaintained between 30% and 70%. Chow and water are provided ad libitumfor the duration of the study. In each test, animals are randomlyassigned across treatment groups.

Test compounds are prepared and administered according to the followingprocedures. A composition provided by the present disclosure isdissolved or suspended in an appropriate vehicle for administration. Theamount of a levodopa prodrug administered can range, for example, from0.01 mg/kg to 100 mg/kg. As a positive control, clozapine (1 mg/kg) isdissolved in 10% DMSO and administered i.p. at a dose volume of 10 ml/kgat 30 min prior to PCP (phencyclidine) injection. PCP (5 mg/kg) isdissolved in sterile injectable water and administered i.p. at a dosevolume of 10 mL/kg.

The Open Filed (OF) test is used to assess both anxiety and locomotorbehavior. The open field chambers are Plexiglas square chamberssurrounded by infrared photobeams (16×16×16) to measure horizontal andvertical activity. The analysis is configured to divide the open fieldinto a center and periphery zone. Distance traveled is measured fromhorizontal beam breaks as a mouse moves and rearing activity is measuredfrom vertical beam breaks.

Mice are acclimated to the activity experimental room for at least 1 hto prior to testing. Eight animals are tested in each run. Mice areinjected with water or a levodopa prodrug, placed in holding cages for30 min, and then in the OF chamber for 30 min, removed from the OFchamber and injected with either water or PCP and returned to the OFchambers for a 60-minute session. A different group of mice are injectedwith either 10% DMSO or clozapine and placed in the OF chamber for 30min, removed from the OF chamber and injected with PCP (5 mg/kg), andreturned to the OF chambers for a 60-minute session.

Data is analyzed by analysis of variance (ANOVA) followed by post-hoccomparisons with Fisher Tests when appropriate. Baseline activity ismeasured during the first 30 min of the test prior to PCP injection.PCP-induced activity is measured during the 60 min following PCPinjection. Statistical outliers that fall above or below 2 standarddeviations from the mean are removed from the final analysis. An effectis considered significant if p<0.05.

Auditory Startle and Prepulse Inhibition of Startle (PPI)

Young, adult male C57B1/6J mice are used in this study. Mice arereceived at 6-weeks of age. Upon receipt, mice are assigned uniqueidentification numbers (tail marked) and are group housed in standardmouse cages. All animals remain housed in groups of four during thestudy. All mice are acclimated to the colony room for at least two weeksprior to testing and are subsequently tested at an average age of 8-9weeks of age. During the period of acclimation, mice are examined on aregular basis, handled, and weighed to assure adequate health andsuitability. Mice are maintained on a 12 h/12 h light/dark cycle. Theroom temperature is maintained between 20° C. and 23° C. with a relativehumidity between 30% and 70%. Feed and water are provided ad libitumduring the study. For testing, animals are randomly assigned acrosstreatment groups and balanced by PPI chamber.

Test compounds are prepared and administered according to the followingprocedures. A composition provided by the present disclosure isdissolved in an appropriate solvent for administration. An appropriateamount of a levodopa prodrug is administered i.p. 30 minutes prior totesting the normal mouse-PPI portion of the study. As a positivecontrol, clozapine (3 mg/kg) is dissolved in 1% Tween and administeredi.p. 60 min prior to testing the PCP-PPI portion of the study. PCP (8mg/kg phencyclidine) is dissolved in sterile injectable water andadministered 30 minutes prior to testing. PCP is delivered at a dosevolume of 10 mL/kg.

Acoustic startle measures an unconditioned reflex response to externalauditory stimulation. PPI consisting of an inhibited startle response(reduction in amplitude) to an auditory stimulation following thepresentation of a weak auditory stimulus or prepulse, has been used as atool for the assessment of deficiencies in sensory-motor gating, such asthose seen in schizophrenia. Mice are placed in the PPI chamber (MedAssociates) for a 5 min session of white noise (70 dB) habituation. Atest session begins immediately after the 5 min acclimation period. Thesession starts with a habituation block of 6 presentations of thestartle stimulus alone, followed by 10 PPI blocks of 6 different typesof trials. Trial types are: null (no stimuli), startle (120 dB), startleplus prepulse (4, 8 and 12 dB over background noise i.e., 74, 78 or 82dB) and prepulse alone (82 dB). Trial types are presented at randomwithin each block. Each trial begins with a 50 ms null period duringwhich baseline movements are recorded. There is a subsequent 20 msperiod during which prepulse stimuli are presented and responses to theprepulse measured. Following a 100 ms pause, the startle stimuli arepresented for 40 ms and responses are recorded for 100 ms from startleonset. Responses are sampled every ms. The inter-trial interval isvariable with an average of 15 s (range from 10 to 20 s). In startlealone trials the basic auditory startle is measured and in prepulse plusstartle trials the amount of inhibition of the normal startle isdetermined and expressed as a percentage of the basic startle response(from startle alone trials), excluding the startle response of the firsthabituation block.

For the normal mouse-PPI portion of the study, C57BL/6J mice are treatedwith vehicle, haloperidol, or composition comprising a levodopa prodrugand placed back in their holding cages. Thirty min following injectionof vehicle or haloperidol and 60 min following injection of vehicle or alevodopa prodrug, normal mouse-PPI testing begins.

For the PCP-PPI portion of the study, C57BL/6J mice are treated withvehicle, clozapine, or a levodopa prodrug and returned to their holdingcages. Thirty min later, all treatment groups are injected with vehicleor PCP. Thirty min following vehicle or PCP injection, PPI testingbegins.

Data is analyzed using appropriate statistical methods. For the PPIanalysis, all mice that have a startle response below 100 are removedfrom the analysis.

Example 36 Animal Model for Assessing Therapeutic Efficacy of LevodopaProdrugs for Treating Huntington's Disease Neuroprotective Effects in aTransgenic Mouse Model of Huntington's Disease

Transgenic HD mice of the N171-82Q strain and non-transgenic littermatesare treated with a levodopa prodrug or a vehicle from 10 weeks of age.The mice are placed on a rotating rod (“rotarod”). The length of time atwhich a mouse falls from the rotarod is recorded as a measure of motorcoordination. The total distance traveled by a mouse is also recorded asa measure of overall locomotion. Mice administered levodopa prodrugsthat are neuroprotective in the N171-82Q transgenic HD mouse modelremain on the rotarod for a longer period of time and travel furtherthan mice administered vehicle.

Malonate Model of Huntington's Disease

A series of reversible and irreversible inhibitors of enzymes involvedin energy generating pathways has been used to generate animal modelsfor neurodegenerative diseases such as Parkinson's and Huntington'sdiseases. In particular, inhibitors of succinate dehydrogenase, anenzyme that impacts cellular energy homeostasis, has been used togenerate a model for Huntington's disease (Brouillet et al., J.Neurochem. 1993, 60, 356-359; Beal et al., J. Neurosci. 1993,13,4181-4192; Henshaw et al., Brain Research 1994, 647, 161-166; and Bealet al., J. Neurochem. 1993, 61, 1147-1150). The enzyme succinatedehydrogenase plays a central role in both the tricarboxylic acid cycleas well as the electron transport chain in mitochondria. Malonate is areversible inhibitor of succinate dehydrogenase. Intrastriatalinjections of malonate in rats have been shown to produce dose dependentstriatal excitotoxic lesions that are attenuated by both competitive andnoncompetitive NMDA antagonists (Henshaw et al., Brain Research 1994,647, 161-166). For example, the glutamate release inhibitor,lamotrigine, also attenuates the lesions. Co-injection with succinateblocks the lesions, consistent with an effect on succinatedehydrogenase. The lesions are accompanied by a significant reduction inATP levels as well as a significant increase in lactate levels in vivoas shown by chemical shift resonance imaging (Beal et al., J. Neurochem.1993, 61, 1147-1150). The lesions produce the same pattern of cellularsparing, which is seen in Huntington's disease, supporting malonatechallenge as a useful model for the neuropathologic and neurochemicalfeatures of Huntington's disease.

To evaluate the effect of levodopa prodrug in this malonate model forHuntington's disease, levodopa prodrug is administered at an appropriatedose, dosing interval, and route, to male Sprague-Dawley rats. A prodrugis administered for two weeks prior to the administration of malonateand then for an additional week prior to sacrifice. Malonate isdissolved in distilled deionized water and the pH adjusted to 7.4 with0.1 M HCl. Intrastriatal injections of 1.5 μL of 3 μmol malonate aremade into the left striatum at the level of the Bregma 2.4 mm lateral tothe midline and 4.5 mm ventral to the dura. Animals are sacrificed at 7days by decapitation and the brains quickly removed and placed in icecold 0.9% saline solution. Brains are sectioned at 2 mm intervals in abrain mold. Slices are then placed posterior side down in 2%2,3,5-tiphenyltetrazolium chloride. Slices are stained in the dark atroom temperature for 30 min and then removed and placed in 4%paraformaldehyde pH 7.3. Lesions, noted by pale staining, are evaluatedon the posterior surface of each section. The measurements are validatedby comparison with measurements obtained on adjacent Nissl stainsections.

Compounds exhibiting a neuroprotective effect and therefore potentiallyuseful in treating Huntington's disease show a reduction inmalonate-induced lesions.

Example 37 Animal Models of Depression Forced Swim Test in Rats

Male Wistar rats weighting 230-270 g are acclimated to the colony roomfor a minimum of 1 week, handled daily for at least 4 days andhabituated to saline injections for 2 days before the experiments.

Two glass cylinders (20 cm dia×40 cm height) are separated by blackopaque partitions and filled with water at about 24° C. to a depth of 30cm. At this depth a rat cannot stand on the cylinder bottom. The waterlevel is 10 cm from the top. Water is changed before each animal isplaced into the water tank. An experimental session consists of twotrials. During the conditioning trial, rats are gently placed into thecylinders for 15 min. After the trail, rats are dried and placed into awarm cage with the paper towels for 10-15 min before being returned totheir home cages. Twenty-four hours later, for the test trial, animalsare placed again into the cylinders for a 5-min test session. Tests arevideo taped for subsequent quantitative behavioral analysis. Thefrequency and/or total duration are calculated for each of the followingcategories: passive/immobile behavior (floating is scored when an animalremains in the water with all four limbs motionless, except foroccasional alternate movements of paws and tail necessary to preventsinking and to keep head/nose above the water); active/mobile behaviors(swimming characterized by rigorous movements with all four legs;paddling characterized by floating with rhythmical simultaneous kicksand occasional pushes off the wall to give speed and direction to thedrift), including escape-oriented behaviors (climbing characterized byintense movements with all four limbs, with the two forepaws breakingthe surface of the water and being directed against the walls of thecylinder; diving characterized by movements towards the bottom of thecylinder with the rat's head below its hind limbs), and self-directedbehaviors (headshakes, vigorous headshakes to get water off the snoutand eyes; wiping, rubbing water away from the snout). In addition, atthe end of each test trial, fecal boli are counted. A test compound,control, or positive control (e.g., imipramine) is administered prior tothe test.

Tail Suspension Test in Mice

Mice are housed in standard laboratory cages and acclimated. Mice aremoved from the housing room to the testing area in their home cages andallowed to adapt to the new environment for at least 1 h before testing.Immobility is induced by tail suspension according to the procedure ofSteru et al., Psychopharmacology 1985, 85, 367-370. Mice are lyingindividually on a paper adhesive tape, 65 cm above a tabletop. Tape isplaced approximately 1 cm from the tip of the tail. Animals are allowedto hang for 6 min and the duration of immobility is recorded. Mice areconsidered immobile only when hanging passively and completelymotionless. Mice from these experiments are sued one week later inlocomotor activity studies. A test compound, control, or positivecontrol (e.g., imipramine) is administered prior to the test.

Locomotor Activity

The spontaneous locomotor activity of mice is measured in photoresistoractometers (circular cages, 25 cm in dia, 15 cm high, two light sources,two photoresistors), wherein the animals are placed individually 1 hafter injection of a test compound. The number of crossings of lightbeams is measured during the first 30 min of the experimental session.The first measurement is performed 6 min after placing an animal intothe actometer.

The spontaneous locomotor activity of rats is measured in photoresistoractometers (40 cm×40 cm×25 cm, two light sources, two photoresistors),where the animals are placed after administration of a test compound.The number of crossings of light beams is measured during the first 30min of an experimental session. The first measurement is performed 5 minafter placing an animal in the actometer.

Finally, it should be noted that there are alternative ways ofimplementing the embodiments disclosed herein. Accordingly, the presentembodiments are to be considered as illustrative and not restrictive.Furthermore, the claims are not to be limited to the details givenherein, and are entitled their full scope and equivalents thereof.

1. A compound of the formula:

stereoisomers thereof, pharmaceutically acceptable salts of any of theforegoing, or pharmaceutically acceptable solvates of any of theforegoing, wherein: R¹ is chosen from C₁₋₈ alkyl, substituted C₁₋₈alkyl, C₁₋₈ alkoxy, substituted C₁₋₈ alkoxy, C₃₋₇ cycloalkyl,substituted C₃₋₇ cycloalkyl, C₃₋₇ cycloalkoxy, substituted C₃₋₇cycloalkoxy, phenyl, substituted phenyl, phenyloxy, and substitutedphenyloxy; R² and R³ are independently chosen from C₁₋₈ alkyl,substituted C₁₋₈ alkyl, C₁₋₈ alkoxy, substituted C₁₋₈ alkoxy, C₃₋₇cycloalkyl, and substituted C₃₋₇ cycloalkyl; and R⁴ and R⁵ areindependently chosen from hydrogen, C₁₋₈ alkyl, and substituted C₁₋₈alkyl; wherein each substituent group is independently chosen fromhalogen, —OH, —COOH, —CN, —CF₃, ═O, —NO₂, C₁₋₃ alkoxy, C₁₋₃ alkyl, and—NR¹⁰ ₂ wherein each R¹⁰ is independently chosen from hydrogen and C₁₋₃alkyl.
 2. The compound of claim 1, wherein R¹ is chosen from C₁₋₅ alkyl,C₁₋₅ alkoxy, phenyl, phenyloxy, C₃₋₇ cycloalkyl, and C₃₋₇ cycloalkoxy;each of R² and R³ is chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; and R⁴ andR⁵ are independently chosen from hydrogen and methyl.
 3. The compound ofclaim 1, wherein: R¹ is chosen from C₁₋₅ alkyl, C₁₋₅ alkoxy, phenyl,phenyloxy, C₃₋₇ cycloalkyl, and C₃₋₇ cycloalkoxy; each of R² and R³ ischosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is C₁₋₃ alkyl and R⁵ ishydrogen.
 4. The compound of claim 3, wherein the stereochemistry at thecarbon atom to which R⁴ is bonded is of the (S)-configuration.
 5. Thecompound of claim 3, wherein the stereochemistry at the carbon atom towhich R⁴ is bonded is of the (R)-configuration.
 6. The compound of claim3, wherein R⁴ is methyl.
 7. The compound of claim 3, wherein thecompound is chosen from: (2R)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;(2R)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;(2R)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;(2R)-2phenylcarbonyloxypropyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;(2S)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;(2S)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;(2S)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;(2S)-2phenylcarbonyloxypropyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;a pharmaceutically acceptable salt of any of the foregoing, and apharmaceutically acceptable solvate of any of the foregoing.
 8. Thecompound of claim 1, wherein: R¹ is chosen from C₁₋₅ alkyl, C₁₋₅ alkoxy,phenyl, phenyloxy, C₃₋₇ cycloalkyl, and C₃₋₇ cycloalkoxy; each of R² andR³ is chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; R⁴ is hydrogen; and R⁵ isC₁₋₃ alkyl.
 9. The compound of claim 8, wherein the stereochemistry atthe carbon atom to which R⁵ is bonded is of the (S)-configuration. 10.The compound of claim 8, wherein the stereochemistry at the carbon atomto which R⁵ is bonded is of the (R)-configuration.
 11. The compound ofclaim 8, wherein R⁵ is methyl.
 12. The compound of claim 8, wherein thecompound is chosen from: (1R)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;(1R)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;(1R)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;(1R)-2phenylcarbonyloxypropyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;(1S)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;(1S)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;(1S)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;(1S)-2phenylcarbonyloxypropyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;a pharmaceutically acceptable salt of any of the foregoing, and apharmaceutically acceptable solvate of any of the foregoing.
 13. Thecompound of claim 1, wherein: R¹ is chosen from C₁₋₅ alkyl, C₁₋₅ alkoxy,phenyl, phenyloxy, C₃₋₇ cycloalkyl, and C₃₋₇ cycloalkoxy; each of R² andR³ is chosen from C₁₋₅ alkyl and C₁₋₅ alkoxy; and R⁴ and R⁵ areindependently C₁₋₃ alkyl.
 14. The compound of claim 13, wherein thestereochemistry at the carbon atom to which R⁴ is bonded is of the(S)-configuration, and the stereochemistry at the carbon atom to whichR⁵ is bonded is of the (S)-configuration.
 15. The compound of claim 13,wherein the stereochemistry at the carbon atom to which R⁴ is bonded isof the (S)-configuration, and the stereochemistry at the carbon atom towhich R⁵ is bonded is of the (R)-configuration.
 16. The compound ofclaim 13, wherein the stereochemistry at the carbon atom to which R⁴ isbonded is of the (R)-configuration, and the stereochemistry at thecarbon atom to which R⁵ is bonded is of the (S)-configuration.
 17. Thecompound of claim 13, wherein the stereochemistry at the carbon atom towhich R⁴ is bonded is of the (R)-configuration, and the stereochemistryat the carbon atom to which R⁵ is bonded is of the (R)-configuration.18. The compound of claim 13, wherein each of R⁴ and R⁵ is methyl. 19.The compound of claim 13, wherein the compound is chosen from:(1S,2S)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;(1S,2S)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;(1S,2S)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;(1S,2S)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;(1S,2R)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;(1S,2R)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;(1S,2R)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;(1S,2R)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;(1R,2S)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;(1R,2S)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;(1R,2S)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;(1R,2S)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;(1R,2R)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate;(1R,2R)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoate;(1R,2R)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoate;(1R,2R)-1-methyl-2-phenylcarbonyloxypropyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;a pharmaceutically acceptable salt of any of the foregoing, and apharmaceutically acceptable solvate of any of the foregoing.
 20. Thecompound of claim 1, wherein the compound is chosen from:(1R)-1-methyl-2-phenylcarbonyloxyethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R)-1-methyl-2-phenylcarbonyloxyethyl(2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R)-1-methyl-2-phenylcarbonyloxyethyl(2S)-2-amino-3-[3,4-bis(2-methylpropanoyloxy)phenyl]propanoatehydrochloride; (1R)-1-methyl-2-phenylcarbonyloxyethyl(2S)-2-[(tert-butoxy)carbonylamino]-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoate;(1R)-2-acetyloxy-1-methylethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R)-2-acetyloxy-1-methylethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate hydrogenfumarate; (1R)-1-methyl-2-(2-methylpropanoyloxy)ethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R)-1-methyl-2-phenylcarbonyloxyethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R)-2-ethoxycarbonyloxy-1-methylethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R)-2-acetyloxy-1-methylethyl(2S)-2-amino-3-[3,4-bis(methylethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R)-1-methyl-2-phenylcarbonyloxyethyl(2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R)-2-ethoxycarbonyloxy-1-methylethyl(2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R)-2-isopropoxycarbonyloxy-1-methylethyl(2S)-2-amino-3-(3,4-bis(isopropoxycarbonyloxy)phenyl)propanoatehydrochloride; (1R)-1-methyl-2-phenylcarbonyloxyethyl(2S)-2-amino-3-[3,4-bis(isobutanoyloxy)phenyl]propanoate hydrochloride;(1R)-1-methyl-2-phenylcarbonyloxyethyl(2S)-2-amino-3-[3,4-bis(2,2-dimethylpropanoyloxy)phenyl]propanoatehydrochloride; (1R,2R)-2-acetoxy-1-methylpropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R,2R)-1-methyl-2-(2-methylpropanoyloxy)propyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R,2R)-2-isobutoxycarbonyloxy-1-methylpropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R,2R)-2-isopropoxycarbonyloxy-1-methylpropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R,2R)-1-methyl-2-pentyloxycarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R,2R)-2-hexyloxycarbonyloxy-1-methylpropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R,2R)-2-acetoxy-1-methylpropyl(2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R,2R)-1-methyl-2-(2-methylpropanoyloxy)propyl(2S)-2-amino-3-[3,4-bis(isopropoxycarbonyloxy)phenyl]propanoatehydrochloride; (2R)-2-acetyloxypropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (2R)-2-acetyloxypropyl(2S)-2-amino-3-[3,4-bis(methylethoxycarbonyloxy)phenyl]propanoatehydrochloride; (2R)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; and (2R)-2-phenylcarbonyloxypropyl(2S)-2-amino-3-(3,4-bis(methylethoxycarbonyloxy)phenyl]propanoatehydrochloride.
 21. The compound of claim 1, wherein the compound ischosen from: (1R)-1-methyl-2-phenylcarbonyloxyethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R,2R)-2-acetoxy-1-methylpropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R,2R)-1-methyl-2-(2-methylpropanoyloxy)propyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R,2R)-2-isopropoxycarbonyloxy-1-methylpropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (2R)-2-acetyloxypropyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R)-2-acetyloxy-1-methylethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride; (1R)-2-acetyloxy-1-methylethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoate hydrogenfumarate; and (1R)-1-methyl-2-(2-methylpropanoyloxy)ethyl(2S)-2-amino-3-[3,4-bis(ethoxycarbonyloxy)phenyl]propanoatehydrochloride.
 22. A pharmaceutical composition comprising at least onepharmaceutically acceptable vehicle and a therapeutically effectiveamount for treating a disease in a patient of at least one compound ofclaim 1; wherein the disease is chosen from Parkinson's disease,depression, attention deficit disorder, schizophrenia, manic depression,cognitive impairment disorders, restless legs syndrome, periodic limbmovement disorders, tardive dyskinesia, Huntington's disease, Tourette'ssyndrome, hypertension, addictive disorders, congestive heart failure,stroke, excessive daytime sleepiness, dystonia, and memory and learningdeficit and loss.
 23. The pharmaceutical composition of claim 22,wherein the pharmaceutical composition is a sustained release oraldosage formulation.
 24. A method of treating a disease in a patientcomprising administering to a patient in need of such treatment apharmaceutical composition of claim 22; wherein the disease is chosenfrom Parkinson's disease, depression, attention deficit disorder,schizophrenia, manic depression, cognitive impairment disorders,restless legs syndrome, periodic limb movement disorders, tardivedyskinesia, Huntington's disease, Tourette's syndrome, hypertension,addictive disorders, congestive heart failure, stroke, excessive daytimesleepiness, dystonia, and memory and learning deficit or loss.
 25. Themethod of claim 24, wherein the pharmaceutical composition is asustained release oral dosage formulation.